Test: Cause and Effect - GMAT MCQ

(A) Nothing is mentioned about the thoroughness of research conducted by big companies before they invest in startups.

(B) The passage does not necessarily imply that a startup cannot be taken seriously unless some reputed company has stake in it. In formal logic terms, "All A is B" does not necessarily mean "Only A is B".

(C) This is again an implicit statement that cannot be concluded directly from the passage. All fundamentals do not necessarily need to be perfect for big companies to invest in smaller ones. The passage mentions only two precise aspects of such decision-making.

(D) The passage mentions only a single example meaning this generalization cannot be logically drawn from the passage.

(E) Correct. This answer follows clearly and directly from the first two lines of the passage; if investment by a big IT firm means that business focus and products are on target then it must follow that these are requisite attributes for a big IT company to invest in a startup

(A) Europeans are more likely to wear safety belts than are people in the United States.
Incorrect. This option weakens the argument by presenting an alternate explanation for the difference in the severity of the injuries. If Europeans are more likely to wear safety belts, naturally they are expected to have less severe injuries in accidents. Does the ‘kind of seat belt’ have a role to play in the difference in the severity of the injuries? We are not sure now. Thus, the conclusion suggesting changes in the standards for safety belt design comes into question.

(B) Unlike United States drivers, European drivers receive training in how best to react in the event of an accident to minimize injuries to themselves and to their passengers.
Incorrect. This option weakens the argument by presenting an alternate explanation for the difference in the severity of the injuries. If European drivers and not US drivers are trained in the way mentioned, naturally Europeans are expected to have less severe injuries in accidents. This casts doubt on whether safety seat belts have any role to play in the difference in the severity of the injuries.

(C) Cars built for the European market tend to have more sturdy construction than do cars built for the United States market.
Incorrect. This option weakens the argument by presenting an alternate explanation for the difference in the severity of the injuries. If European cars are sturdier than the US cars, naturally Europeans are expected to have less severe injuries in accidents since the cars will be able to protect the passengers better. This option too casts doubt on whether safety seat belts have any role to play in the difference in the severity of the injuries.

The first three options highlight a very common way of weakening such an argument – presenting an alternate cause that probably leads to the effect.

(D) Automobile passengers in the United States have a greater statistical chance of being involved in an accident than do passengers in Europe.
Correct. This option has no impact on the argument. The option suggests that on average, automobile passengers in the US get involved in more accidents than do passengers in Europe. However, regardless of the number of accidents passengers get involved in, the difference in the ‘severity of the injuries’ still stands. And from the argument, it does seem that difference in the kinds of safety belts has a role to play here. Thus, the argument stands as is.

(E) States that have recently begun requiring the European safety belt have experienced no reduction in the average severity of injuries suffered by passengers in automobile accidents.
Incorrect. This option weakens the argument by presenting a situation in which the suggestion presented in the conclusion hasn’t worked. If the states that have started using European safety belts have not experienced any benefit from the shift, we become doubtful whether any changes in the safety seat belt design will help the US.

This is a “Useful to Evaluate” question, which borrows many tactics from traditional Strengthen/Weaken questions. (The leverage phrase in the question stem, “which… would be most helpful in evaluating…” clearly indicates this question type.) With Useful to Evaluate questions, "Minding the Gap" is critical. The correct answer will either plug the gap (Strengthen) or explode the gap (Weaken). Trap answers will not address the logical gap.

The primary logical gap in this question is the disconnect between the data and the conclusion. While the data tells us that workers who spend 20+ hours in front of a computer monitor exhibit a 12% reduction in cognitive abilities after 15 years, we don’t know if that 12% reduction is actually caused by the exposure or if it might be caused by something else during those 15 years. (For example, what if most people who sit at a job for 15 years see a much greater decline in cognitive ability? A mere 12% reduction could actually show that sitting in front of computer monitors keep your brain relatively sharp! Alternatively, what if it isn’t the radiation that causes the decline; instead, sitting in one position for 15 years is what actually causes it?) We need to find the answer choice that addresses this gap in some way.

Answer choice A “moves the goalposts” on the reader, getting the reader to think that the reversibility (or permanency) of the damage matters. This introduces an emotional, human component to the story, but one that isn’t related to the logical gap. A is a trap answer.

Answer choice B traps those who misunderstand what the problem is asking. While questioning the 15-year period might be interesting if someone is evaluating the study as a whole, the question stem explicitly asks us to identify the question that can best help us evaluate the specific reasoning presented. Answer choice B does not address the logical gap between the data and the conclusion.

At first glance, answer choice C looks like it helps us to compare the rates of cognitive decline across a spectrum of various occupational tasks. However, answer choice C is a Yes/No question that doesn’t really help us much: if the answer is “No”, then it appears that occupational tasks might not determine cognitive decline. But if we answer “Yes”, then we only know that there is a relationship between occupational tasks and cognitive decline. We don’t know what that relationship is, and we have no data points to compare. Answer choice C gets us started, but is very weak.

Answer choice D doesn’t mind the logical gap. In fact, the problem states that the “average” cognitive decline was 12%. This data point implies that either (1) all of the participants somehow had the exact same 12% drop, or (2) some people were above and others were below the 12% average. That is how “average” works. It is very likely that the data was spread around the 12% average, so D tells us very little. And D certainly doesn’t address the lack of clear causal link between monitor exposure and cognitive decline.

Answer choice E gives us a strong comparative that can help us prove (or disprove) a potential causal link. The answer to the question in this answer choice would give us a measurable number against which we can compare the 12% cognitive decline. Whether the cognitive decline rate of the average worker is higher than, lower than, or equal to the measured 12% decline, such data could give us strong leverage to evaluate the reasoning in the argument. Answer choice E is the correct answer.

Main Point: Living together before marriage leads to divorce.
Assumption: There was no other factor involved.

(A) In comparison with more conservative minded people, more liberal minded people tend to be more open to living together before marriage and more open to getting divorced. - Correct. It was the mindset of the people that caused the divorce and living together before marriage was not exactly the main cause.

(B) In some countries the divorce rate has steadily decreased over the past 30 years. - Incorrect. Irrelevant.

(C) Couples who live together before getting married have an opportunity to learn to work together as a team before they get married. - Incorrect. Out of focus. This option talks about the events before marriage.

(D) For preventing divorce, there is no substitute for having good communication skills. - Incorrect. Irrelevant.

(E) For many couples who live together before getting married, marriage itself does not result in significant changes to their lifestyles. - Incorrect. May be it was not the change in lifestyle, but something else may have caused the divorce. Still the conclusion that living together before marriage is most likely to cause divorce is not weakened.

(A) Incorrect. The first thing to notice here is that this option talks about competitive-athlete-category as a whole. It doesn’t distinguish between competitive swimmers and other competitive athletes. Since the whole point of the passage is to explain the higher incidence of asthma among competitive swimmers vis-à-vis other competitive athletes, an option that doesn’t distinguish between these two categories of competitive athletes will always be irrelevant.
Even if we change ‘competitive athletes’ to ‘competitive athletes who are not competitive swimmers’, the option will still be incorrect. The changed option means that we don’t have a biased population of young people coming into other competitive athletics (biased here means more likely to have asthma). The option thus means that there is no reason to expect a higher than normal incidence of asthma among competitive athletes who are not swimmers. However, this option fails to give any reason for higher incidence of asthma among competitive swimmers or any reason why the presence of chlorine cannot lead to higher incidence of asthma among competitive swimmers.
Even if we change ‘competitive athletes’ to ‘competitive swimmers’, the option will still be incorrect. Rather, in this case, the negation of this option will be a possible answer.

(B) Incorrect. This option is in the opposite direction to the correct answer. If other competitive athletes are rarely exposed to chlorine and, we know that, competitive swimmers are frequently exposed to chlorine, then it seems reasonable to expect that chlorine leads to higher incidence of asthma among competitive swimmers. This expectation is opposite to the stated last line. 

(C) Incorrect. For the same reason as stated in option A. This option talks about competitive-athletes-category as a whole.

(D) Correct. If physicians routinely recommended competitive swimming to children with asthma, then we can expect a higher proportion of people with asthma in competitive swimming than in other sports. Thus, this option provides an alternate reason for the higher incidence of asthma among competitive swimmers. A higher proportion of people joining competitive swimming have asthma than joining other competitive athletics. This can explain the higher incidence of asthma among competitive swimmers than among other competitive athletes. Thus, the presence of chlorine in swimming pools may not be the explanation for the higher incidence of asthma among competitive swimmers.

(E) Incorrect. Again, this option is incorrect for the reason stated in option A: it talks about the category of competitive athletes as a whole. In case no distinction is made between competitive swimming and other competitive sports, then whatever is applicable for competitive swimming must be applicable for other competitive sports too. Thus, this scenario will not give us any reason to expect a higher incidence of asthma among competitive swimmers.

To determine which option most strongly supports the researchers' hypothesis, let's analyze each option and see how it relates to the hypothesis:

(A) SV40 is widely used as a research tool in cancer laboratories.

• This option does not provide direct support for the hypothesis that the contaminated polio vaccine was the source of the SV40 virus found in mesotheliomas decades later. It merely mentions the use of SV40 as a research tool, which is not directly relevant to the hypothesis.

(B) Changes in the technique of manufacturing the vaccine now prevent contamination with SV40.

• This option suggests that the current manufacturing technique of the polio vaccine prevents contamination with SV40. While this information is important for vaccine safety, it does not provide strong support for the hypothesis about the source of SV40 found in mesotheliomas.

(C) Recently discovered samples of the vaccine dating from 1960 still show traces of the virus.

• This option suggests that recently discovered samples of the contaminated polio vaccine still show traces of the SV40 virus. While this information is interesting, it does not directly support the hypothesis about the source of SV40 found in mesotheliomas decades later.

(D) In a small percentage of cases of mesothelioma, there is no history of exposure to asbestos.

• This option provides information about a small percentage of mesothelioma cases where there is no history of asbestos exposure. While this information is relevant to the disease, it does not directly support the hypothesis about the source of SV40 found in mesotheliomas.

(E) In Finland, where the polio vaccine was never contaminated, samples from mesotheliomas do not contain SV40.

• This option directly supports the researchers' hypothesis. It states that in Finland, where the polio vaccine was never contaminated with SV40, samples from mesotheliomas do not contain SV40. This suggests a strong correlation between the contaminated polio vaccine and the presence of SV40 in mesotheliomas.

Therefore, option (E) provides the strongest support for the researchers' hypothesis and is the most relevant piece of information in relation to the source of SV40 found in mesotheliomas.

The argument presents a counterargument to the widely held belief that eating chocolate directly causes acne. It suggests that the observed correlation between eating chocolate and experiencing acne outbreaks may be a result of a common underlying factor, which is stress. Here's a breakdown of the main points and the reasoning behind the chosen answer:

1. Acne and Chocolate Consumption: The argument acknowledges that many people who are susceptible to acne believe that eating large amounts of chocolate leads to acne outbreaks.

2. Mistaking Effect for Cause: The argument suggests that common wisdom may have mistaken the effect (acne outbreaks) for the cause (eating chocolate). It implies that there might be another factor at play.

3. Hormonal Changes and Stress: Recent scientific studies indicate that hormonal changes associated with stress can cause acne. This suggests that stress, rather than chocolate consumption, may be the primary cause of acne outbreaks.

4. Chocolate Consumption and Stress: There is evidence that people who are fond of chocolate tend to eat more chocolate when they are under stress. This implies that the increased chocolate consumption observed in individuals under stress may be a result of the stress itself.

Based on these points, the most accurate expression of the main point is (D) because it highlights that the relationship between chocolate consumption and acne is less likely to be a direct cause-effect relationship. Instead, both chocolate consumption and acne are more likely to be caused by stress.

The argument against the automobile manufacturer's claim is that they are substituting steel frames with cheaper plastic components due to corporate profit motives rather than consumer demand for lighter cars with crumple zones. The fact that carbon reinforced tubing is not available as an option despite being lighter and stronger supports this argument.

Option B strengthens the argument against the manufacturer's claim by providing a reason for automobile companies not to use carbon tubing:

• Automobile companies are reluctant to invest in high volume industrial technology to produce carbon tubing until profits from the sale of small scale commercial carbon products, such as bicycle frames, have stabilized.

This statement implies that automobile companies are prioritizing profit considerations over consumer demand for lighter cars with crumple zones, as they are waiting for profits from other carbon products to stabilize before investing in carbon tubing for automobiles.

The manager's argument is that the company's change in policy (offering unlimited free shipping) caused the 25 percent increase in mail-order sales. To strengthen this argument, we need additional evidence that supports the claim that the policy change was the primary cause of the increase.

(A) Mail-order sales have been decreasing for companies that do not offer unlimited free shipping.

• This statement strengthens the argument because it suggests that the unlimited free shipping policy is a significant factor in attracting customers and increasing sales. If companies that don't offer unlimited free shipping are seeing a decrease in sales, it is more likely that the policy change caused the increase in sales for the manager's company.

(B) The company did not widely advertise its change in policy.

• This statement does not strengthen the argument because it could suggest that the increase in sales was due to factors other than the shipping policy change. If the policy change wasn't widely advertised, it is less likely to be the primary cause of the sales increase.

(C) The company's profits from mail-order sales have increased since the change in policy.

• This statement does not directly strengthen the argument because it only indicates that the company is making more profits from mail-order sales, but it doesn't address whether the policy change was the cause of the sales increase.

(D) The company's change in policy occurred well after its competitors started offering unlimited free shipping.

• This statement does not strengthen the argument because it suggests that the company's policy change may not have been the primary cause for the sales increase. If competitors already offered unlimited free shipping, it is possible that other factors contributed to the sales increase.

(E) Most companies offer free shipping only on mail-order purchases over $50.

• This statement does not directly strengthen the argument because it only provides information about other companies' policies and does not indicate whether the manager's company's policy change was the cause of the sales increase.

Thus, option A most strengthens the manager's argument as it provides evidence that the policy change was a significant factor in attracting customers and increasing sales.

The argument in the passage states that emotional stress causes serious health problems, including high blood pressure, cardiac complications, obesity, and nervousness. This conclusion is based on a study that found people with high emotional stress levels are more obese and nervous than people with lower levels of emotional stress.

To evaluate the assumptions on which the argument rests, let's examine each answer choice:

(A) Obesity and nervousness can lead to serious health problems.

• This statement is not an assumption necessary for the argument. The argument already claims that emotional stress causes health problems, including obesity and nervousness. It does not rely on the assumption that obesity and nervousness themselves cause serious health problems.

(B) Emotionally stressed out people are aware of the various health problems attributed to emotional stress, including high blood pressure and cardiac complications.

• The argument does not assume that people with high levels of emotional stress are aware of the health problems it causes. The conclusion is based on the results of a study, not on the awareness of the people involved.

(C) Equivalent numbers of people with high and low levels of emotional stress were surveyed for the study.

• While it is important for a study to have a balanced sample size, the argument does not hinge on this assumption. Even if the number of people surveyed in each group were different, the results could still show that people with higher levels of emotional stress are more obese and nervous.

(D) Obesity and nervousness do not make individuals less capable to deal with emotionally stressful situations.

• This statement is an assumption the argument relies upon. If obesity and nervousness were to make individuals less capable of dealing with emotionally stressful situations, it could create a confounding factor, meaning that the relationship between emotional stress and these health problems might not be causal. By assuming that obesity and nervousness do not affect individuals' ability to handle emotional stress, the argument can conclude that emotional stress is the cause of these health problems.

(E) Emotionally stressed out people who had encountered an emotionally stressful situation immediately before responding to the survey were more obese and nervous than the people form same group who had not encountered any emotionally stressful situation for a few days.

• This statement is not an assumption necessary for the argument. The argument is based on a comparison between people with high levels of emotional stress and those with low levels, not on the difference in obesity and nervousness within the high-stress group based on recent experiences.