Test: Assumption - GMAT MCQ

The popular view is that Ozone layer’s depletion is real, as certain as Neil Armstrong's landing on the moon. While that may be the case, the attribution of such depletion to man-made chemicals is not true. Mount Pinatubo in the Philippines spewed forth more than a thousand times the amount of ozone-depleting chemicals in one volcanic eruption than all the fluorocarbons manufactured by wicked, diabolical and insensitive corporations in history. Mankind can't possibly equal the output of even one eruption from Pinatubo, much less 4 billion years' worth of them, so how can it be held responsible for destroying ozone.

Which of the following is an assumption on which the argument of the author depends?

Argument Analysis

Conclusion:

The attribution of depletion of Ozone layer to man-made chemicals is not true.

Premises:

1. Mount Pinatubo in the Philippines spewed forth more than a thousand times the amount of ozone-depleting chemicals in one volcanic eruption than all the fluorocarbons manufactured by wicked, diabolical and insensitive corporations in history
2. Mankind can't possibly equal the output of even one eruption from Pinatubo, much less 4 billion years' worth of them

Here, premises 1 and 2 are set of dependent information pieces and comprise a single reason used by the author to arrive at the conclusion. In essence, it means that:

Ozone depleting chemicals produced by Mount Pinatubo is much greater (probably billion of times) than ozone depleting chemicals (fluorocarbons) produced by mankind.

This reason is used to signal that man-made chemicals can only play an insignificant role in the depletion of Ozone layer.

Therefore, (Conclusion) Man-made chemicals can’t be held responsible for ozone layer depletion.

Pre-Thinking

As we can see, the argument is talking in terms of the amount of ODC ( Ozone Depleting Chemicals), not in terms of their impact on the ozone layer. This is a missing link needed to establish the correctness of the argument.

So, a statement like “ODCs generated by volcanic eruptions have the same effect on the Ozone as ODCs generated by mankind”, would complete the argument.

However, this is not a must-be-true statement. Why? Because we know that the quantity of volcanic ODCs is probably billions of times greater than man-made ODCs, therefore, even if volcanic ODCs have much less effect than man-made ODCs, our conclusion would still hold.

Therefore, our only requirement can be that volcanic ODCs have at least some effect on the Ozone layer.

However, why would ODCs be called so if they don’t have any effect on Ozone layer. So, they have to have some impact. Therefore, the only way our conclusion won’t hold is in below two situations:

1. Volcanic ODCs don’t reach Ozone layer due to some reason (hypothetical) –
   1. Probably because due to their high temperature. they react with some chemical as soon as they reach atmosphere and this reaction snaps their ability to deplete Ozone layer
   2. Their chemical or physical properties is different from man-made ODCs and these properties prevent them from reaching Ozone layer
2. Volcanic ODCs can’t deplete unless the depletion has been started by man-made ODCs. Suppose, Ozone layer exists in a very stable state – this state cannot be affected by volcanic ODCs. However, once man-made ODCs can start reactions with this stable state of Ozone and deplete it, which, in turn, make it reactive even to Volcanic ODCs.

In both the situations above, our conclusion won’t hold. Therefore, negation of either of the two assumptions could be a valid answer.

Answer Choices

A

It would take mankind more than 4 billion years to destroy Ozone.

So what? We are concerned with the cause of depletion, not the time-frame. Incorrect.

B

Each molecule of ozone depleting chemical released during an eruption of Mount Pinatubo destroys the same quantity of ozone as a molecule of fluorocarbons.

As we analyzed in the pre-thinking, this is not required. Even if a molecule of volcanic chemical destroys much less ozone than a man-made chemical, the conclusion will still hold. Therefore, this is not a must be true statement. Thus, Incorrect.

C

The amount of ozone-depleting chemicals released during a single eruption in Mount Pinatubo is much higher than the quantity of fluorocarbons produced by the companies

This can be inferred from the passage. Therefore, this presents no new information and thus, cannot be an assumption. Incorrect.

D

The molecular structure of ozone-depleting chemicals released during a volcanic eruption does not prevent them from reaching the stratosphere, the layer of the atmosphere where the ozone layer resides.

This is in line with our prethinking. If these volcanic ODCs don’t reach ozone layer, then the reasoning of the argument breaks down. Therefore, this is a must-be-true statement for the argument to hold. Correct.

E

The rate at which an ozone depleting chemical, whether man-made or released in a volcanic eruption, is released is not more important in the destruction of ozone layer than the quantity of chemicals released.

Given this statement is in a negative form “not more”. Let’s negate it and see if the conclusion breaks down. We can see that even if rate is more important than the quantity, it doesn’t impact the conclusion, since we don’t know whether slow rate depletes Ozone layer more or fast rate depletes more. Therefore, Incorrect.

When construction workers start taking breaks from work to keep from burning out, a cyclical chain of events starts. Such breaks during work hours lead to increased work load, which in turn prompts construction managers to exert pressure on the workers to finish their tasks as soon as possible. This, in turn, leads construction workers to take longer and more frequent breaks.

The cyclical chain of events described above could not result unless which of the following were true?

Argument Analysis

Pre-Thinking

Conclusion Clarification

The passage concludes that a cyclical chain of events starts due to a particular event. Now, the question stem says “The cyclical chain of events described above could not result unless which of the following were true”. Therefore, we need to find an assumption or a condition that must be true for the cycle of events to take place.

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify the conclusion. To do so, we will look at the logical structure, focusing on each of the links between the events. 

Thus, to falsify the conclusion, we need to break the linkages and hence prevent the cyclic occurrence of events. The assumption then will be that these conditions do not exist.

Linkage#1 – Breaks by construction workers lead to increased workload.

• Falsification Condition:  For some reason the breaks do not lead to increased workload
  • Instance: For example, if the construction managers plan the work by considering the break time, the cycle might break.
  • Assumption: Construction managers do not plan the work in a manner that takes the worker break time into consideration.

Linkage#2 – Longer and more frequent breaks lead to an increase in work load

• Falsification Condition:  Taking longer and more frequent breaks leads to significant improvements in the efficiency of the workers.
  • Instance: For example, during breaks workers consume energy drinks and participate in fun activities arranged by the construction company, activities that physically and mentally rejuvenate them.
  • Assumption: Taking more frequent breaks does not lead to significant improvements in the efficiency of the workers.

With this understanding in mind, let's take a look at the option statements.

Answer Choices

A

Managers discourage workers from taking any kind of breaks, even for preventing burnouts, during working hours.

Incorrect - Opposite

If managers discourage workers, it might reduce the chances of the occurrence of the cyclic events. This consideration goes against the conclusion.

B

Many workers do not take work breaks and do not believe that work breaks help them increase their productivity.

Incorrect - Opposite

This option is similar to option A and it might reduce the chances of the occurrence of the cyclic events. This consideration goes against the conclusion.

C

Many construction companies do not deduct money from workers’ wages for taking frequent breaks from work.

Incorrect - Not a must-be-true

This option is not a must-be-true statement since even if companies deduct money from workers’ wages, it does not imply that the workers will not take breaks and therefore it doesn’t break the cyclic occurrence of events.The statement can be considered a strengthener but not an assumption.

D

Construction companies whose workers do not take frequent breaks have good gyms where the employees can work out and evade burnout.

Incorrect - Irrelevant 

This option talks about cases which do not involve the mentioned cyclical chain of events.

E

When managers estimate timings to complete a project, they do not account for breaks taken by workers.

Correct

This option is parallel to the assumption we identified in the pre-thinking phase under linkage 1.

The Circle Multiplex has seen tremendous growth in the number of customers since it signed an exclusive contract with a leading distributor. For the last seven months, unlike previous months, almost all the shows have been booked completely. A number of customers have even been turned away for most of the shows. Consequently, the management proposes to increase its profits by raising the ticket prices slightly above the competition’s as it believes that invariably the Multiplex will be able to fill its capacity.

Which of the following statements is an assumption made by the management of The Circle Multiplex?

Argument Analysis

Pre-Thinking

Conclusion Clarification

The management of CM proposes (concludes) that in order to increase its profits, the ticket prices be raised slightly above the competition’s. Multiplex

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify this conclusion.  To do so, we will look at the logical structure, focusing on linkage 1 and the conclusion.  We will understand the condition under which the conclusion is falsified.  The assumption then will be that the condition does not exist.

Linkage #1 & 2 –

• Falsification Condition:  The fact that shows have been booked completely in the past doesn’t support that the multiplex will continue to fill the capacity in the future despite a slight increase in the price of the ticket. What if a slight increase in prices leads to a massive decline in number of customers? In such a case, the conclusion will not hold.

• Assumption: A significant proportion of CM’s customers are not very sensitive to ticket prices.

With this pre-thinking in mind, let’s evaluate the answer choices.

Answer Choices

A

The Circle Multiplex has lower ticket prices than other Multiplexes in the region.

Incorrect - Irrelevant

The plan distinctly states raising the price of the tickets to slightly above the competition’s. So it’s irrelevant whether currently its price is the same or lower than that of other’s.

B

Factors other than ticket prices such as ambience are very important for the customers in choosing the Multiplex.

Incorrect - Not a must be true

To the extent this choice impacts the logic of the argument, it possibly suggests that management’s plan may not be out of sync with the Multiplex customers in general who have other important considerations besides the ticket price. Therefore, it does increase our belief in the conclusion, but it is not a must be true statement as even if  the other factors are not very important, they could still be important and the conclusion is still strengthened by the negation of this choice.

C

No existing customer of The Circle Multiplex is going to shift for minor economic considerations.

Incorrect - Irrelevant

The change in the price has only been referred to in terms of increase in price to a level slightly above that of the competitors. Accordingly, we don’t know whether the change in the ticket price is going to be minor; for instance, if currently the price of CM’s tickets is well below that of the competition’s then the absolute change could be major. Therefore, the author has not factored in this piece of information while drawing the conclusion.

D

Not a significant number of customers of The Circle Multiplex are extremely sensitive to ticket prices.

Correct

This choice is written along the lines of our pre-thinking per Linkage.  If a significant number of customers are extremely sensitive to ticket prices, then most of them are likely to shift when the prices are increased. In such a case, the revenues may decline considerably and accordingly the profits may also decline.

E

Most other Multiplexes around The Circle Multiplex run most of the shows with less than half the capacity filled.

Incorrect - Irrelevant

This option is about the other multiplexes. The argument is about the proposal aimed at increasing the profits of the CM and hence this piece of information is irrelevant to the argument.

Opponents of free university-education in the country feel that allocating resources to providing free post-high school education would be wastage of the tax-payers money. They claim that no significant economic benefit will be realized from the same since most people with degrees will likely do such jobs in the country for which they are over-qualified and that the most bright and academically oriented people from economically underprivileged backgrounds do anyway benefit from the various scholarships already in place by the government.

Which of the following is an assumption on which the opponents’ argument is based?

Argument Analysis

Pre-Thinking

Conclusion Clarification

The question stem requires us to find a fundamental assumption made by the opponents of free university-education. These opponents conclude that allocating resources to providing free post-high school education would be wastage of the tax-payers money.

Pre-Thinking Approach

To pre-think assumptions, we will falsify the conclusion / intermediate conclusion (IC) or look for scenarios under which they are no longer valid even when the given premises are true. The assumption then will be that such conditions don’t exist.

Linkage #1: Most people with degrees will likely do such jobs in the country for which they are over-qualified.

• Falsification condition: What if, jobs requiring  UE grow  as more people start getting university degrees?  Then the IC won’t be valid that there will be no significant EB from FUE. Accordingly, the critics assume that:
  • Assumption 1: Jobs requiring UE won’t grow significantly enough to absorb the increase in the number of university graduates.

Linkage #2: No significant EB from FUE

• Falsification condition: What if, even though there is no significant EB from FUE, there are other benefits that justify the expenditure on free post-high school education? TP money might be well spent to obtain these benefits. Then the conclusion won’t be valid that allocating resources in the stated fashion will be a waste of TP money.
  • Assumption 2: There are no other important benefits that can over-ride the lack of a significant economic benefit in determining whether the TP money has been well-spent.

With this understanding in mind, let’s take a look at the option statements.

Answer Choices

A

The money that the government currently collects in taxes is not sufficient to finance  free- university education in the country.

Incorrect - Irrelevant

The argument isn’t concerned with whether there is sufficient money to fund FUE, but with whether it’s a waste to fund FUE if money is available to do so.

B

As the free university-education program is implemented, the economy will not generate enough jobs commensurate with the educational level of the graduates.

Correct

This choice is written along the lines of our pre-thinking per Linkage #1, Assumption 1.

C

The most bright and academically oriented people normally do not have the economic means to pursue university education.

Incorrect - Irrelevant

The argument doesn’t talk about all the people who fall in the most bright and academically oriented group. It talks about only the most bright and AO people from EUB.

D

Currently, there is a shortage of suitable jobs in the country for people with university level education.

Incorrect - Irrelevant

The argument only mentions that most people with degrees will be overqualified for jobs in the future if FUE is provided. It doesn’t comment about the current status.

E

Many people who obtain degrees after the free university-education program is implemented will not choose to work within the country.

Incorrect - Opposite

The opponents predict that most people with degree will likely do jobs inside the country. So, this information goes against their prediction.

Citing that popular sports such as cricket and football have been able to sustain themselves without any financial aid from the government, some people believe that if people have enough interest in an art form, they will be willing to pay the money to experience it. Therefore, they reason that even if the government stops art subsidies, ultimately only those art forms will survive that most people actually have interest in.

Which of the following is an assumption on which the conclusion of the people mentioned in the above argument depends?

Argument Analysis

Pre-Thinking

Conclusion Clarification

There is no given conclusion in the argument. However, the question stem asks us to find the assumption in people’s argument. Therefore, we’ll regard their assertion as the conclusion. Their conclusion is that even if the government stops art subsidies, ultimately only those art forms will survive that most people actually have interest in.  They believe that if people have enough interest in an art form, they will be willing to pay the money to experience it. The basis of their belief is the fact that popular sports sustain themselves without any financial aid from the government.

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify this conclusion.To do so, we will look at the logical structure, focusing on linkage 1, linkage 2 and the conclusion.We will understand the condition under which the conclusion is falsified.The assumption then will be that the condition does not exist.Also note that as we focus on a particular linkage, we will keep the other linkages in mind as well.

Linkage#1

• Falsification Condition:  What if art forms are not comparable to sports in terms of the interest they are capable of drawing from people? If this were true, the conclusion would be falsified.
  • Assumption: Art forms and  sports are comparable in terms of the interest they are capable of drawing from people.

Linkage#2 

• Falsification Condition:  Even if people want to pay to to experience an art form, we don’t know whether they would actually be able to pay. What if people are unable to support the art form that they are interested in despite their willingness to do so? They may not be sufficiently financially well off to support the art form. In such a case, the conclusion will be falsified.
  • Assumption: People interested in a particular art-form have the means to pay to experience it.

With this understanding in mind, let's move to the option statements. 

Answer Choices

A

While providing subsidies, the government does not take in to account whether most people actually have interest in that art form.

Incorrect - Irrelevant

The argument concludes on the scenario in which the government stops art subsidies. The government’s considerations while providing subsidies are not relevant.

B

People pay huge amounts to witness live sporting events such as cricket, football, hockey etc.

Incorrect - Irrelevant

The argument does not require any assumption regarding the magnitude of the amount people pay to witness their favorite sports.

C

Currently, there are numerous art forms that receive subsidies but that have failed to garner people’s interest in them.

Incorrect - Irrelevant

The conclusion is drawn on the art forms that people have interest in. Art forms that receive subsidies but have failed to earn people’s interest are not relevant.

D

Currently most of the institutions that receive art subsidies from the government could be alternatively funded by the philanthropic organizations backed by business houses.

Incorrect - Irrelevant

Alternative sources of funding are irrelevant to the conclusion that only those art forms will survive that most people actually have interest in.

E

Most people who have interests in various art forms have the means to pay to witness it.

Correct

This choice is written along the lines of our pre-thinking per Linkage #2. 

During the Civil War, railroads were the quickest way to transport troops across locations. However, the railroads were originally used to transport agricultural products, particularly wheat, from their place of production to their place of sale. Clearly, the militarization of the railroads must have affected the transport of agricultural goods during the war, thereby also impacting the sales of such products. So, sales of wheat during the Civil War must have been considerably lower than sales of wheat before the war.

Which of the following is an assumption made by the author?

Argument Analysis

Pre-Thinking

Conclusion Clarification

N/A

Pre-Thinking Approach

To pre-think assumptions, we will falsify the conclusion / intermediate conclusion (IC) or look for scenarios under which they are no longer valid; i.e. conditions under which sale of wheat wouldn’t have been lower during CW than before it. The assumption then will be that such conditions don’t exist.

Linkage 1

• Falsification condition 1:What if there was an expansion of RR before CW? Then the IC won’t be valid that militarization of RR would have affected the transportation and sale of AP as there might have been enough RR capacity to cater to both military and agricultural needs.
  • Assumption 1: There wasn’t spare RR capacity which could fulfil agricultural needs post militarization.

Linkage 2

• Falsification condition 2:What if, even if RR originally transported AP, before the CW the primary means of transportation of AP, especially wheat, wasn’t RR? Then, even if the militarization of RR affected the transport and sale of AP, it is not necessary that the effect was significant or considerable.
  • Assumption 2: Significant amount of wheat used to be transported by RR before the CW.
• Falsification condition 3: What if wheat was eventually being grown across the country so that there was little or no need to transport it through RR? Then the conclusion won’t be valid that a problem with transportation of AP affected the sales of wheat.
  • Assumption 3:There was a need to transport wheat using RR during the CW.

With this understanding in mind, let’s take a look at the option statements.

Answer Choices

A

Sales of wheat after the war were greater than sales of wheat during the war.

Incorrect - Irrelevant

This is not relevant as it talks about sales of wheat after the war, which we are not interested in.

B

The amount of wheat produced in the country during the war was less than the amount produced before the war.

Incorrect - Irrelevant

A comparison of amount of wheat produced isn’t relevant.

C

The railroads were set up for the purpose of transporting agricultural goods.

Incorrect - Irrelevant

The passage only mentions that RR were originally used for transporting AP; their original purpose could have been anything.

D

Before the war, a significant amount of the wheat that was sold was transported via the railroads.

Correct

This choice is written along the lines of our pre-thinking per Linkage #2, Assumption # 2.

E

Wheat that could not be sold could not be utilized in any other way.

Incorrect - Irrelevant

The passage isn’t concerned with the utilization of unsold wheat at all.

Advisor: The city of Benzaria should discontinue the requirement from all schools to provide video recordings of classroom sessions to the students. The cost implications to maintain such a facility are quite significant for the schools, and the benefit is non-existent as can be seen from the fact that since the implementation of the plan, the difference in the test scores of students in Benzaria and those of students in Karamal has not come down even though Karamal has not implemented this program.

Critic: I disagree as the test scores in Karamal have improved. The implementation of the program in Benzaria has forced the government in Karamal to maintain better school standards in order to compete with Benzaria for federal government funds, the allocation of which is determined by average student test scores in the city.

Which of the following statements is an assumption underlying the critic’s argument?

Argument Analysis

Pre-Thinking

Conclusion Clarification

We are given two conclusions in the argument. The question stem asks us to find the assumption in the critic’s argument. The critic disagrees with the advisor’s conclusion. Therefore, the critic concludes that Benzaria should continue RVR.

Pre-Thinking Approach

To pre-think assumptions, we will falsify the critic’s conclusion or look for scenarios under which it is no longer valid even when the given premises are true. The assumption then will be that such conditions don’t exist.

Please note that the critic’s opinion goes against the advisor’s. Therefore, let’s understand the advisor’s opinion fully.

Linkage #1: Difference in the test scores of Benzaria and Karamal hasn’t reduced

What if TS in both B and K have improved? For example, it is possible that the average test scores in Benzaria were at 50% and those in Karamal at 80%. The difference is that of 30%. However, because of the institution of the RVR, the test scores in Benzaria have risen to 60% and incidentally, in Karamal to 90%.  Now, even though the difference hasn’t come down, the test scores in Benzaria have improved.  So the advisor cannot conclude that benefit from RVR is non-existent.

• Advisor’s Assumption: Test-scores in both Benzaria and Karamal haven’t improved.

Keeping in mind the above understanding, let’s take a look at the critic’s argument.

Linkage #3: Implementation of RVR in B has led to government of K maintaining better school standards.

From the critic’s argument, we can understand that the critic is attributing the lack of decrease in the difference of the test scores of the two cities to the improved test scores of Karamal. However, what if the better school standards in Karamal due to RVR in Benzaria haven’t positively impacted the test scores? If they haven’t, then the critic can’t draw a link between the two and conclude that there is some benefit from RVR or that RVR should continue.

• Assumption 1: Better school standards in Karamal have impacted the test scores positively.

With this understanding in mind, let’s take a look at the option statements.

Answer Choices

A

The better school standards in the city of Karamal have led to better test scores for its students.

Correct

This choice is written along the lines of our pre-thinking per Linkage #3, Assumption 1.

B

The requirement of recording classroom sessions has led schools in Benzaria to hire better quality instructors.

Incorrect - Not a must be true

This is not a must-be-true statement for the critic’s conclusion to hold. RVR could be beneficial even if better quality instructors haven’t been hired.

C

Test scores are not the only way to compare student performance across different schools.

Incorrect - Opposite

This option weakens the critic’s conclusion by undermining the importance of test scores.

D

Student test scores in Benzaria cannot be increased significantly without the requirement on the schools to record classroom sessions.

Incorrect - Irrelevant

We aren’t concerned with whether TS can be improved otherwise or not. We are only looking at whether RVR is beneficial for TS or not.

E

Student attendance in the classrooms in Benzaria hasn’t decreased after the introduction of the requirement to record classroom sessions.

Incorrect - Irrelevant

This is not relevant as the passage doesn’t provide any link between attendance and TS.

Geometrical patterns are often utilized in intelligence tests, typically with the test-taker being given a specific pattern and then being asked to identify a matching pattern from a given set of images. However, pattern recognition is a measure of precognition abilities. Therefore, geometrical patterns should not be used in IQ tests. 

Which of the following is an assumption made by the author?

Argument Analysis

Pre-Thinking

Conclusion Clarification

N/A.

Pre-Thinking Approach

To prethink assumptions we will falsify the conclusion or look for scenarios under which the conclusion is no longer valid; i.e. conditions under which the conclusion that Geometrical Patterns should not be used in IQ test may not hold. 

Linkage 1:   Pattern recognition is a measure of precognition abilities.

On the basis of the above linkage, the author concludes that geometrical patterns should not be used in IQ tests.

• Falsification Condition: What if tests that measure precognition abilities can also measure IQ? Surely, the author cannot make the given recommendation then. Therefore, the author assumes that this scenario does not exist. Hence the assumption is:
  • Tests that measure precognition abilities cannot measure IQ.

With this understanding in mind, let's take a look at the option statements.

Answer Choices

A

Those who take IQ tests are interested in measuring their precognition abilities.

Incorrect - Irrelevant

This the preferences & interests of IQ test takers are no relevant to whether test measuring  pre-cognition abilities can test a person’s IQ.

B

Measuring precognition abilities is currently an objective of IQ tests.

Incorrect - Opposite

If the objective of IQ tests is to measure precognition abilities, it weakens the belief that geometrical patterns should not be used in IQ tests.

c

A test that measures precognition abilities cannot also test intelligence.

Correct

This choice matches our prethinking and is a must be true statement for the conclusion to hold.

D

Some test-makers are more interested in measuring precognitive abilities than intelligence.

Incorrect - Irrelevant

The interests of certain test makers is irrelevant to determining whether test measuring precognition abilities can also measure IQ. 

E

IQ tests cannot be used for testing in fields in which precognitive abilities are required. 

Incorrect - Irrelevant

The argument is not about the applicability of IQ test in fields in which precognitive abilities are required. So the information given in this choice is completely irrelevant.

In an experiment undertaken by the management of a company to determine how to best motivate its employees, certain employees were sent weekly e-mails appreciating their work for two months. At the end of the two months, it was found in a survey conducted on all the employees that the ones not sent the e-mails on average reported less satisfaction from their work than the ones sent the mails. Therefore, in the long run, to keep the morale and productivity of its employees high, a company should appreciate the work of its employees on a regular basis.

Which of the following is an assumption on which the argument relies? 

Argument Analysis

Pre-Thinking

Conclusion Clarification

To keep M and P high in the long run, companies should appreciate the work of Es regularly.

Pre-Thinking Approach

To pre-think assumptions, we will examine linkage 1 and falsify the conclusion or look for scenarios under which the conclusion is no longer valid. The assumption will be that these conditions don’t exist.

Linkage 1

• Falsification condition1: The author draws a causal link between the experiment and the survey results. However, what if something else led to the lower satisfaction levels in the employees that were not sent the mails? In such a condition, the conclusion will not hold.
  • Assumption 1: There was no other factor, besides appreciation, that could have significantly impacted the satisfaction levels of the employees.

• Falsification condition 2: What if it’s not possible to regularly appreciate employees? In such a condition, the conclusion will not hold.
  • Assumption 2: It is possible to regularly appreciate employees.

• Falsification Condition 3: What if regular appreciation brings in complacency in the employees? In such a condition, the conclusion will not hold.
  • Assumption 3: With regular appreciation, the employees will not become complacent in their work.

With this understanding in mind, let’s take a look at the option statements.

Answer Choices

A

In the long run, the employees of a company that critically evaluates the work of its employees are less motivated than those of a company that only appreciates the work of its employees.

Incorrect - Irrelevant

The comparison between Es of a company that critically evaluates the work and that which only appreciates isn’t relevant. The author is concerned with the employees of the same company- those who are appreciated regularly and those who arent’.

B

Eventually, the employees of a company that engages in regular appreciation of its employees’ work will understand the intention behind the appreciation coming their way.

Incorrect - Irrelevant

The author neither states nor implies any link between the awareness of the Es regarding the appreciation and their motivation/productivity levels. It is possible that the appreciation works at a sub-conscious rather than conscious level.

C

There are no other ways to motivate the employees than to regularly appreciate their work.

Incorrect - Irrelevant

The argument is about whether regular appreciation works, not whether there are alternatives methods available or not.

D

Employees whose morale is low cannot generate productive work regularly.

Incorrect - Irrelevant

Satisfaction/morale and productivity are linked with regular appreciation in the argument; however, the author does not link productivity and morale to each other.

In the long run, regular appreciation of their work will not make the employees casual in their attitude towards work.

Correct

This choice is written along the lines of our pre-thinking per Linkage #1, Assumption 3.

The high rate of depression among people in countries that do not receive much sunlight most of the year prompted researchers at the University of Frankphyl to study the link between a lack of vitamin D, which is found naturally in sunlight, and the incidence of depression. The study found that in patients with a relatively severe degree of depression, the level of vitamin D was lower than in patients with a milder degree of depression. The researchers hence concluded that people in such countries can avert depression by including vitamin D supplements in their diet.

Which of the following is required for the conclusion drawn by the researchers to hold true?

Argument Analysis

Pre-Thinking

Conclusion Clarification

This is a causal argument.

The conclusion states that people in countries that do not receive much sunlight most of the year can avoid depression by including vitamin D supplements in their diet. The conclusion is based on a study that found that in patients with a relatively severe degree of depression, the level of vitamin D was lower than in patients with a milder degree of depression.

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify this conclusion.  To do so, we will look at the logical structure, focusing on linkage 1 and the conclusion.  We will understand the condition under which the conclusion is falsified.  The assumption then will be that the condition does not exist.

Linkage#1 – The study found that in patients with a relatively severe degree of depression, the level of vitamin D was lower than in patients with a milder degree of depression.

• Falsification Condition:  What if the severe degree of depression in a person causes the level of vitamin D to decrease in the patient? If this were true, then the conclusion will be falsified. Please note that this is a fundamental assumption made in causal arguments that the effect does not lead to the cause.
  • Assumption: The severity of depression in a person doesn’t affect the level of vitamin D in the person.   

With this pre-thinking in mind, let’s evaluate the answer choices.

Answer Choices

A

There is a significant difference in the effect that vitamin D obtained directly from sunlight and that obtained from dietary supplements has on the health of a patient suffering from depression. 

Incorrect - Opposite

If the effect of vitamin D on a patient’s health varies depending upon its source, the conclusion is weakened since now people in countries that do not receive much sunlight may not be able to avoid depression by including vitamin D supplements in their diet.

B

Patients with the most severe degree of depression belonged to countries that do not receive sunlight up to extended periods of six months.

Incorrect - No new information

As regards the severity of depression, the argument only makes a relative comparison between two kinds of patients - those with severe and milder depression. However, this choice talks about the most severe degree of depression.

C

Both people with a severe degree of depression and those with a mild degree of depression belonged to the same economic strata. 

Incorrect - Irrelevant

The economic status of the people is not relevant to the conclusion that is based on the link between the lack of vitamin D and the incidence of depression.

d

The lack of vitamin D is not triggered by depression in patients.

Correct

This choice is written along the lines of our pre-thinking per Linkage #1.  By eliminating the possibility of depression causing the lack of vitamin D, it defends the argument from a potential weakener. 

E

The required dose for vitamin D supplements is significantly higher for patients with severe depression than for patients with mild depression.

Incorrect - Irrelevant

The relative dose of vitamin D is not relevant to the argument since it doesn’t tell us whether patients can avoid depression by taking such doses.

Two years ago, the state of Lonsia declared the goal of reducing the number of un-recycled soda cans to half. The un-recycled soda cans were about 10 per person then. Currently the soda cans that are un-recycled are only 5 per person. Clearly, the state has met its goal.

Which of the following is an assumption on which the argument depends?

Argument Analysis

Pre-Thinking

Conclusion Clarification

N/A

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify the conclusion. The assumptions will then be that the falsification conditions do not exist.

The way to falsify the conclusion will be to identify reasons to show that Lonsia has not met its goal of reducing the number of un-recycled cans to half. To do so, we will look at the logical structure, focusing on the linkage 1.

Linkage #1

Note that the logical structure shows that the goal talks about an absolute reduction in the number of un-recycled soda cans while the premise talks about a reduction in the number of un-recycled soda cans per person.

• Falsifying condition – A reason that shows that Lonsia has not met its goal of reducing un-recycled cans to half.

• For example, if the number of people doubled in the two years, the number of un-recycled cans could still be the same even though the number of recycled cans could have halved.
• Assumption - The number of people in Lonsia has not gone up significantly in the last two years.

Now that we have a fair understanding of the argument, let’s take a look at the option statements.

Answer Choices

A

People are increasingly becoming aware of the harmful effects of drinking soda.

Incorrect - Irrelevant 

The argument talks about whether the goal of reducing the number of un-recycled soda cans to half has been achieved or not. The reason behind the reduction in soda consumption is not  something on which the conclusion depends

B

There is little damage to the overall soft drink industry due to the negative publicity generated by the recycling campaign.

Incorrect - Irrelevant 

Even if there has been a significant amount of damage to the soft-drink industry, it does not warrant the conclusion that the number of un-recycled soda cans has decreased significantly. For instance, what if the number of overall soda cans purchased has decreased but at the same time the number of recycled soda cans has decreased substantially?

C

Lonsia is not the only state that is concerned about recycling.

Incorrect - Irrelevant

The option statement talks about recycling in other states. We are concerned with only Lonsia.

D

The total population of the state of Lonsia has not increased substantially in the past two years.

Correct

This option matches the assumption that we identified in our pre-thinking linkage #1 analysis.

e

The per-capita consumption of soda in the state of Lonsia has not increased during the past two years.

Incorrect - Irrelevant 

This option talks about soda consumption while the argument is only concerned with un-recycled soda cans/person.

While handsets get hyped, a typical U.S. consumer watches more than 5 hours of TV a day, according to Nielsen, and even younger adults from 18 to 24 years of age—the supposed digital generation—spend 3 hours and 30 minutes watching TV daily compared to only 49 minutes on the Web and 20 minutes on mobile phones. Therefore, since most media is still consumed through TV, the claims that TV as a medium for advertising has lost some importance are certainly incorrect.

Which of the following must be true for the above argument to hold?

Argument Analysis

Pre-Thinking

Conclusion Clarification

The author concludes that the claims that TV as a medium for advertising has lost some importance are certainly incorrect. In other words, TV as a medium for advertisement has not lost any importance. The conclusion is based on the fact that most of the media is still consumed through TV as consumers spend more time on TV in comparison to web and mobile.

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify this conclusion.  To do so, we will look at the logical structure, focusing on linkage 1 and the conclusion.  We will understand the condition under which the conclusion is falsified.  The assumption then will be that the condition does not exist.

Linkage#1 –

• Falsification Condition:  Even if we know that a person spends more time on watching TV than on web and mobile, can we be sure that the person actually watches the advertisements displayed on the TV? What if the person switches the channel during an advertisement? In this case, even though he is spending more time on TV than on web and mobile, he is not watching any advertisements. Hence, the conclusion that TV as a medium for advertisement has not lost any importance doesn’t hold.  Another important point to note here is that “losing importance” is a comparative statement. What if the population used to watch 6 hours of TV before? In this case too, the conclusion will not hold.

• Assumption: The amount of advertisement consumption through a medium is directly proportion to the amount of media consumption on that medium, i.e. when a person spends time on TV, he/ she does spend time watching advertisements. 

With this understanding in mind, let's take a look at the option statements.

Answer Choices

A

The number of advertisements that can be shown per unit of time spent is not significantly greater in TVs than in other mediums.

Incorrect - Irrelevant

The negation of this statement provides strength to the argument at hand. Clearly, this choice does not provide any support to the conclusion and hence cannot be the assumption of the argument.

B

The impact of an advertisement served on a medium is directly proportional to the amount of time the advertisement is displayed/shown.

Incorrect - Irrelevant

This option implies that if an advertisement is of a longer time duration it would have more impact and vice-versa. However, the author doesn’t make any connection between the probability of the featuring of such advertisements and the total time spent on consuming media through a particular medium.

C

The importance of a medium of advertisement does not depend only on the time spent by the consumers on that medium.

Incorrect - Opposite

To the extent this choice has any impact on the argument, it weakens the same as it now opens up the possibility that there may be other factors  as well that determine the importance of a medium of advertisement, thereby potentially diminishing the importance of the only factor (time spent) cited by the author.

D

Most of the time spent watching TV these days is not spent on watching recorded shows which allows skipping of content.

Correct

This choice is written along the lines of our pre-thinking per Linkage #1.  The claim is that people don’t like watching advertisements. By eliminating the possibility that more time spent on TVs is spent watching recorded shows, which allow skipping of content, it defends the argument against a potential weakener.

E

None of the advertisers have recently significantly reduced the amount they spent on advertising on TV.

Incorrect - Irrelevant

This option doesn’t help us conclude anything about the importance of TV as a medium of advertisement. Even if some of the advertisers have significantly reduced their spending on TV, TV as a medium of advertisement may still retain its importance.

Director of TalMart: Our company provides a 90-day without-question return policy on all products sold. Each month on an average, our outlets receive requests for returns on almost 20% of the sales made.  It is clear that because of the ‘without question’ clause, our customers have no incentive to make wiser selections. If customers made better selections to begin with, then we would not see most of these products being returned.

Which of the following is required for the argument to hold?

Argument Analysis

Pre-Thinking

Conclusion Clarification

N/A

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify this conclusion.  To do so, we will look at the logical structure, focusing on linkages 1 and 2.  We will understand the condition under which the conclusion is falsified.  The assumption then will be that that condition does not exist.  Also note that as we focus on a particular linkage, we will keep the other linkages in mind as well.

Linkage#1

• Falsification Condition:  Yes, there is a ‘without question’ clause and returns make up 20% of the sales.  But what if that’s not the reason to make unwise selections? TalMart might deal mostly in low value items where customer involvement isn’t high and as a result people don’t spend too much time in choosing items carefully. Or what if customers aren’t even aware of this clause? If this were true, then the intermediate conclusion will be falsified.
  • Assumption 1: There are no other reasons behind ‘unwise’ selections.
  • Assumption 2: A substantial number of customers are aware of the ‘no question’ clause

Linkage#2 – ‘Without questions’ clause means there is no incentive for customers to make wiser selections

• Falsification Condition:  What if the products sold by TalMart were of a low quality? In that case, returns would occur even if customers selected the products more carefully. 
• • Assumption 3: The high rate of returns is NOT due to inherent problems with the products, which the customers cannot preempt while making purchasing decisions .

With this understanding in mind, let's take a look at the option statements.

Answer Choices

a

A significant number of customers these days are aware of the return or exchange policy of the stores they make purchases from.

Correct

This choice is written along the lines of Assumption 2 in our pre-thinking (per Linkage #1).

B

Not all customers return products even when they are happy with the quality.

Incorrect - No new information

We already know that returns rate is only 20%, so this option doesn’t provide new information.

C

Most of the customers returning the products return them because they later realise that these products are too expensive for them.

Incorrect - Not a must be true

This choice does act as a strengthener as it reinforces the point about making "wiser decisions"; however, it is not a must be true statement as even if price was not a consideration, the customers could make unwise decisions. 

D

Many customers come to the store to exchange the products but end up returning them instead.

Incorrect - Irrelevant

This option tells us how a lot of returns are made but not the reason behind them. We don’t know why customers are coming to the store to exchange the products in the first place.

E

The inherent quality of the products, a factor that the customers cannot successfully gauge at the time of buying, is often a reason for the frequent rate of returns.

Incorrect - Opposite

This option is a weakener as it is written along the lines of the falsification condition mentioned under Linkage #2.

In the last year, a company has lost a few clients and gained a few. But the number of clients lost has been lower than the number of new clients. Also, the average sales for each new client are more than the average sales for each of the other clients. Therefore, it is likely that the company’s average sales per client have been increasing steadily.

Which of the following is required for the above argument to hold?

Argument Analysis

Pre-Thinking

Conclusion Clarification

N/A

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify the conclusion. The way to falsify the conclusion will be to identify reasons to show that it is not likely that the average sales per client have been increasing steadily. To do so, we will look at the logical structure, focusing on linkage 1.

Linkage#1

• Falsifying condition – A reason which shows that higher average sales for each new client (vis-à-vis other clients) do not translate in to an overall steady increase in the total average sales of the company..
  • Instance 1: Average sales per other clients (old clients who were not lost in the period) have been decreasing steadily.
    • Assumption 1: Average sales per ‘other’ clients  have not fallen significantly during the period.
  • Instance 2: Average sales per client added during the period was $500 while average sales per lost client was $2000.
    • Assumption 2: Average sales per client added during the period was not significantly lower than average sales per lost client.

With this understanding in mind, let's take a look at the option statements.

Answer Choices

A

Currently, the total number of clients is more than the total number of clients that existed before the company lost some of its clients.

Incorrect - Irrelevant

The conclusion is only based on a comparison (between the sales per client and number of clients) at the beginning and at the end of the period and we do not know when the “company lost some of its clients”. 

B

The average sales for each new client are at least equal to the average sales for each other client.

Incorrect - No new information

The passage already states that the average sales per new client is more than average sales of other clients.

C

Most of the clients lost were already planning to terminate their relationship with the company.

Incorrect - Irrelevant

The conclusion is based on the analysis of certain statistics - number of clients lost / added and the average sales per client newly gained or existing. The precise reason behind the exits, for instance whether the client exits were pre-planned or not, is not relevant in arriving at the conclusion.

D

There has been no decrease in the quality of the services provided by the company since the company lost some of its clients last year.

Incorrect - Irrelevant

Similar to option C, the option talks about something (quality) which is not a concern of the argument. As stated in the explanation for choice C, the conclusion is based on the analysis of certain mentioned statistics

E

The average sales per client lost were not significantly higher than the average sales for each of the other clients.

Correct

This choice is written along the lines of our pre-thinking per Assumption #2.

Answer Choices

A

The difference between the number of flights of Hexa and the number of flights of Penta did not reduce in the last month.

This option is incorrect.

Irrelevant: No relation between on-time performance and number of flights

B

The market share of Hexa increased in the last month

This option is incorrect.

On-time performance can improve without increase in market share.

C

Penta’s on-time performance did not decline in the last month.

This option is correct.

In- line with pre-thinking. Must be true for the conclusion to be believable.

D

The recently implemented measures by Hexa in order to increase the on-time performance were praised by the analysts, leading to a jump in the stock price.

This option is incorrect.

Irrelevant – praise and jump in stock price.

E

The rewards of the top management at Hexa are linked to the on-time performance of the airline.

This option is incorrect.

Irrelevant – rewards of top management

At a wildlife sanctuary, two methods are usually employed to tranquilize injured animals for treatment: injections and sprays. Although tranquilizer sprays are delivered faster, the overall time taken by the injection to tranquilize an animal is less than that taken by the spray. Therefore, using injections is a more effective method than using the tranquilizer spray.

Which of the following is an assumption on which the argument depends?

Argument Analysis

Pre-Thinking

Conclusion Clarification

The author concludes that using injections is a more effective method than using the spray.  The conclusion is based on the fact that though sprays are delivered faster, the effect of tranquilizer injections occurs faster.

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify this conclusion.  To do so, we will look at the logical structure, focusing on linkage 1 and the conclusion.  We will understand the condition under which the conclusion is falsified.  The assumption then will be that the condition does not exist.

Linkage#1 – (ref. logical structure)

• Falsification Condition:  What if there is no correlation between time taken by a method and its effectiveness? If this were true, then effectiveness of injection and spray as methods of tranquilization cannot be determined by knowing the time taken by the methods to tranquilize. In such a case, the conclusion will be falsified.

• • Assumption: The effectiveness of a method of tranquilization is primarily determined by the time it takes to tranquilize the animal after it has been administered.

With this pre-thinking in mind, let’s evaluate the answer choices.

Answer Choices

A

The effects of tranquilizer injections last much longer than the effects of tranquilizer sprays.

Incorrect - Irrelevant

This option talks about the duration of the effect of a method of tranquilization. But we don’t know whether duration plays a significant role in determining the effectiveness of the method.

B

The effectiveness of a method is inversely proportional to the time it takes to tranquilize an animal.

Correct

This choice is written along the lines of our pre-thinking per Linkage 1. The inverse relationship between effectiveness of a method and time taken by it to tranquilize an animal implies that less time taken by an injection would makes it a more effective method than a spray.

C

Using the tranquilizer spray is not a less effective method than administering tranquilizer injections in the case of sedating large animals for vaccination.

Incorrect - Irrelevant

This option talks about tranquilizing large animals specifically. The passage doesn’t provide any information in this regard.

D

Tranquilizers cannot be delivered faster than currently possible with the use of better technologies.

Incorrect - Irrelevant

This option discusses the role of better technologies to make the delivery of tranquilizers faster than what is possible with current technologies. But we are only talking about the present situation here and not future possibilities. Hence, this choice is irrelevant.

E

The effect of tranquilizer injections occurs faster than that of tranquilizer sprays because the injections are administered intravenously.

Incorrect - Irrelevant

This option talks about the reason why injections have a faster effect than sprays. But the specific reason for this occurrence is not important for the author’s conclusion and hence is not an assumption made by the author.

All intelligent life is multi-cellular, and multi-cellular life is only possible if the cells have the capability of producing energy.  The cells in present day humans, animals, and plants, examples of complex cellular life, require oxygen to break nutrients down and create energy. Since the earth’s environment consisted almost entirely of carbon dioxide prior to the Wiwaxia event, there is little chance that any intelligent life existed on earth prior to the Wiwaxia event.

Which of the following is required to draw the conclusion in the above argument?

Argument Analysis

Pre-Thinking

Conclusion Clarification

The author concludes that there is little chance that any intelligent life existed on earth prior to the WE. The conclusion is based on the facts that present day cells require oxygen to break nutrients down and create energy and that the earth’s environment consisted almost entirely of CO2 before the WE.

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify this conclusion.  To do so, we will look at the logical structure, focusing on linkage 1 and the conclusion.  We will understand the condition under which the conclusion is falsified.  The assumption then will be that the condition does not exist.

Linkage#1 – (ref. logical structure)

• Falsification Condition:  What if the cells had the capability to extract oxygen out of the abundant carbon dioxide present in the earth’s atmosphere before the WE and in turn use that to create energy? Surely, the author won’t be able to conclusively say that a lack of oxygen in the earth’s atmosphere at the time indicates that there is little chance that any intelligent life existed then and thus the conclusion will be falsified.
  • Assumption: Cells existing before the WE had little ability to utilize carbon dioxide in some way to produce energy.

With this pre-thinking in mind, let’s evaluate the answer choices.

Answer Choices

A

Recently discovered evidence suggests that there may have been breathable air on the earth several millennia before the Wiwaxia event.

Incorrect - Opposite

This option weakens the conclusion. If there were breathable air before the WE, it’s possible that intelligent organisms existed even then, as the cells of these organisms could’ve utilized the oxygen to produce energy.

B

The cellular life that existed before the Wiwaxia event had little ability to process atmospheric carbon dioxide, extracting oxygen from the same.

Correct

This choice is written along the lines of our pre-thinking per Linkage #1 assumption. This option suggests that cellular life before the WE had little ability to process atmospheric CO2.

C

After the Wiwaxia event, the carbon dioxide in the earth’s atmosphere decreased by the same amount that the oxygen in the atmosphere increased.

Incorrect - Irrelevant

This option talks about the amount by which carbon dioxide decreased after the WE. But this information is irrelevant as we are interested in knowing only what happened before the WE.

D

Multi-cellular organisms require more energy than single-celled organisms.

Incorrect - Irrelevant

The argument is concerned with only multicellular organisms. This option makes a superfluous comparison between multicellular organisms and single-celled organisms, a piece of information that has no bearing on the argument.

E

Disruptions such as the Wiwaxia event have been observed on other planets that are believed to be capable of supporting life.

Incorrect - Irrelevant

This option talks about the occurrence of disruptions similar to the WE on other planets. However, the conclusion of the argument is concerned with the presence of intelligent life on earth. Hence, the information given in this choice is irrelevant.

The topics included in Financial Accounting books are a reflection of the demands that book publishers are trying to meet. The major deciding factor in the purchase decision of books is the recommendation of university professors. Therefore, the topics included in Financial Accounting books are limited to the general topics of study prescribed by the education board.

Which of the following is an assumption made in drawing the conclusion above?

Argument Analysis

Pre-Thinking

Conclusion Clarification

N/A

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify this conclusion.  To do so, we will look at the logical structure, focusing on the stated linkages.  We will understand the condition under which the conclusion is falsified.  The assumption then will be that the condition does not exist.  Also note that as we focus on a particular linkage, we will keep the other linkages in mind as well.

Linkage#2 – Major deciding factor in purchase decisions is the recommendation of university professors

• Falsification Condition:  What if university professors recommend topics other than the ones prescribed by EB? In that case topics included in FAB can contain these recommended topics as well.
• Assumption: University professors don’t recommend topics other than the general topics of study prescribed by EB.

With this understanding in mind, let's take a look at the option statements.

Answer Choices

A

The general topics of study prescribed by the education board are quite limited in scope.

Incorrect - Irrelevant

The conclusion says that the topics included in FAB are limited to general topics of study prescribed by EB. The limitation declared is regarding the variety of topics in FAB and therefore, nothing needs to be assumed regarding the individual scopes of these topics.

B

University professors do not recommend books that are on topics outside the general topics of study prescribed by the education board.

Correct

This choice is written along the lines of our pre-thinking per Linkage #2.

C

The market for advanced topics of financial accounting will not grow unless there is a huge market for Financial Accounting basics.

Incorrect - Irrelevant

This option is not relevant as the passage doesn’t talk about the market and its growth at all.

D

University professors are much more likely to recommend books covering almost all the relevant topics of study in a subject area than to recommend books covering only a limited range of topics.

Incorrect - Irrelevant

There is not stated or implied link between all the relevant topics of study in a subject and the general topics of study prescribed by the EB. Therefore, the information stated in this choice fails to relate to the passage.

E

It is necessary for publishers to include in their books the general topics of study prescribed by the education board.

Incorrect - Irrelevant

The publishers are not bound by a law/condition to include anything. Their decision is based on the kind of demand in the market- as the passage suggests.

Studies have shown that regularly used household washing machines are teeming with bacteria that find their way onto our clothes and consequently onto us, causing various bacterial infections. Rinsing these machines with bleach is an effective way to get rid of such bacteria. However certain other studies have shown that bleach when used in the undiluted form can severely corrode the metal drum in the machines. Thus, bleach, as long as it is diluted properly, is an effective and safe means of eliminating any health risks from such washing machines.

The argument above will not hold unless which of the following statements holds true?

Argument Analysis

Pre-Thinking

Conclusion Clarification

The author concludes that bleach, as long as it is diluted properly, is an effective and safe means of eliminating any health risks from regularly used HWMs, which are a source of bacterial infections,since bleach, when used in the undiluted form, can severely corrode the metal drum in the machines.

Pre-Thinking Approach

To pre-think assumptions, let’s see how we can falsify this conclusion.  To do so, we will look at the logical structure, focusing on linkage 1 and 2 and the conclusion.  We will understand the condition under which the conclusion is falsified.  The assumption then will be that the condition does not exist.

Linkage#1 – Rinsing these machines with bleach is an effective way to get rid of such bacteria (bacteria that cause bacterial infection).

• Falsification Condition:  What if such washing machines may pose a health risk other than bacterial infection, i.e. any infection other than bacterial infection? In such a case, bleach may not be effective against other health risks.
  • Assumption: Besides bacteria, there are no other disease causing organisms that are found in regularly used HWMs. 

Linkage#2 – Certain other studies have shown that bleach, when used in the undiluted form, can severely corrode the metal drum in the machines.

• Falsification Condition:  What if bleach in diluted form reacts with some other component of the machine and releases harmful chemicals? In such cases, the diluted bleach cannot be considered an effective and safe means to eliminate any health risks.
  • Assumption: The use of diluted bleach in HWMs does not lead to the release of any harmful chemicals that can find their way to humans.   

With this understanding in mind, let’s take a look at the option statements.

Answer Choices

A

The process of diluting bleach with water by a person cannot have harmful effects on the body of that person.

Incorrect -  Irrelevant

The information given in this choice, which relates to how the bleach is diluted and the effect of the same before it’s used in the mentioned washing machines, is irrelevant.

B

Diluted bleach is as effective as concentrated bleach in elimination of bacteria from the washing machines.

Incorrect -  Irrelevant

Although we cannot take it for granted that concentrated bleach means the same as regular bleach, even if we did so, this choice does not give us any concrete information. On negating this statement, we get that diluted bleach is not as effective as concentrated bleach. This could mean that it is either more or less effective than concentrated bleach. Since the negation of the statement does not shatter the conclusion, it is not an assumption.

C

Corrosion of the metal drum in the washing machines is the only negative impact of the use of concentrated bleach in washing machines.

Incorrect -  Irrelevant

The conclusion talks about the effects of diluted bleach whereas this option statement is about the effects of concentrated bleach. Clearly, this option is irrelevant.

D

Diluted bleach does not leave any harmful residues in the washing machine that attach themselves to our clothes.

Correct

This option is written along the lines of our pre-thought assumption identified for linkage 2. If diluted bleach does leave any harmful residue, which attaches itself to clothes, then that can be considered a health risk and thus diluted bleach can’t be considered effective for eliminating all health risks.

E

Rinsing the household washing-machines with bleach is one of the most cost effective methods of eliminating bacteria from these machines.

Incorrect -  Irrelevant

This option concerns itself with cost, which is irrelevant to the argument at hand.