Test: Assumptions - GMAT MCQ

A. The parole board is not legally obligated to accept the recommendations of the violence risk assessment report prepared by a qualified psychologist.
This answer choice is not directly relevant to the assumption being sought. It discusses the legal obligations of the parole board but does not address the effectiveness or necessity of the violence risk assessment itself. Therefore, it is not the correct assumption.

B. A parole screening process will surely be effective if it includes a violence risk assessment conducted by a qualified psychologist.
This answer choice suggests that the inclusion of a violence risk assessment conducted by a qualified psychologist ensures the effectiveness of the parole screening process. This assumption aligns with the conclusion that the assessment is an essential step in an effective parole screening process. If this assumption were not true, it would undermine the conclusion. Therefore, it is a strong candidate for the correct assumption.

C. A prisoner who is not assessed to pose a high risk of re-offending should be released from prison without conditions.
This answer choice introduces a separate condition for the release of prisoners who do not pose a high risk of re-offending. While it may be a valid consideration in the parole process, it is not directly related to the assumption being sought, which pertains to the effectiveness and necessity of the violence risk assessment. Therefore, it is not the correct assumption.

D. Psychologists conducting violence risk assessments are able to identify those prisoners who are unsuitable for early release.
This answer choice directly addresses the assumption being sought. It assumes that psychologists conducting violence risk assessments have the ability to identify prisoners who are unsuitable for early release. If this assumption were not true, it would undermine the conclusion that the assessment is an essential step in an effective parole screening process. Therefore, it is a strong candidate for the correct assumption.

E. Prisoners applying for parole need not undergo a violence risk assessment if they were imprisoned for a non-violent offense.
This answer choice introduces a condition based on the nature of the offense committed by prisoners. However, it does not directly address the assumption being sought, which pertains to the effectiveness and necessity of the violence risk assessment. Therefore, it is not the correct assumption.

After evaluating each answer choice, we can conclude that the correct assumption is (D) "Psychologists conducting violence risk assessments are able to identify those prisoners who are unsuitable for early release." This assumption is necessary for the conclusion that the violence risk assessment is an essential step in an effective parole screening process. If the psychologists conducting the assessments are unable to identify prisoners who are unsuitable for early release, then the assessment would not serve its intended purpose and would not be essential in the process.

Argument:

Temporary-services firms lose business when the economy shows signs of beginning to weaken.
Temporary-services firms gain business when the economy begins to recover.
These firms have begun to gain business in the present weak economy.
Therefore, the economy must be beginning to recover.
Assumption:
B) Temporary-services firms do not gain business when an already weak economy worsens.

Explanation:
To determine whether the conclusion logically follows from the premises, we need to identify the assumption on which the argument depends. In this case, the assumption is that temporary-services firms do not gain business when an already weak economy worsens.

If we negate this assumption and consider the possibility that temporary-services firms can still gain business when the economy worsens, it weakens the argument's conclusion. The increase in business during the weak economy could be due to the worsening economic conditions rather than the beginning of a recovery.

Therefore, to maintain the logical link between the premises and the conclusion, we need to assume that temporary-services firms do not gain business when an already weak economy worsens. This assumption ensures that the increase in business during the weak economy is more likely to be a result of the economy beginning to recover, supporting the argument's conclusion.

Thus, option B is the correct assumption for this argument.

The argument is based on the correlation between unemployment rates and the frequency/duration of vacations taken by full-time workers. It suggests that when unemployment rates are high, full-time workers take fewer and shorter vacations, while during low unemployment rates, they vacation more often and for longer periods. To make this conclusion valid, the argument assumes that workers' perceptions of their own job security are somehow related to the unemployment rate.

Option (A) assumes that those who take the longest vacations during low unemployment have no fear of losing their jobs. This assumption is not necessary for the argument, as the argument does not directly address the fear of losing jobs.

Option (B) about lower travel costs during low unemployment is irrelevant to the relationship between job security perceptions and vacation frequency/duration.

Option (C) assumes that most people prefer full-time jobs, which is not directly relevant to the argument.

Option (D) is the correct assumption. It links workers' perceptions of their job security to the unemployment rate, suggesting that when unemployment rates are high, workers may feel less secure in their jobs, leading to fewer and shorter vacations. Conversely, when unemployment rates are low, workers may feel more secure in their jobs, resulting in more frequent and longer vacations.

Option (E) about workers' fears of losing their jobs increasing recently is not necessary for the argument, as the argument does not discuss the recent timeframe or changes in workers' fears.

Therefore, the correct assumption is (D).

(A) The most effective way to control the numbers of mosquitoes in a given area is to destroy the mosquito larvae in that area.
This assumption is not necessary for the argument because even if there are other effective ways to control mosquitoes, the effectiveness of BTI in reducing mosquito populations would not be undermined.

(B) Populations of mosquitoes are not dependent on a single body of water within an area as a place for their larvae to hatch and develop.
This assumption is not necessary for the argument because even if mosquitoes rely on a single body of water, the effectiveness of BTI in reducing mosquito populations would not be affected.

(C) There are no insect pests besides mosquitoes that pond owners might want to eliminate from in and around their pond.
This assumption is not necessary for the argument because it doesn't affect the claim that BTI can reduce mosquito populations without harming other organisms.

(D) The effectiveness of BTI in destroying mosquito larvae in a pond does not require the pond owner’s strict adherence to specific application procedures.
This assumption is not necessary for the argument because even if strict adherence to specific application procedures is required, it doesn't affect the claim that BTI can reduce mosquito populations without harming other organisms.

(E) The fish, frogs, and beneficial insects in and around a pond-owner’s pond do not depend on mosquito larvae as an important source of food.
This assumption is crucial for the argument because if the fish, frogs, and beneficial insects rely heavily on mosquito larvae as a food source, reducing mosquito populations with BTI could harm these organisms. Therefore, the argument depends on this assumption to hold true.

Therefore, the correct answer is (E) The fish, frogs, and beneficial insects in and around a pond-owner’s pond do not depend on mosquito larvae as an important source of food.

To determine the necessary assumption for the teacher's conclusion to be logically correct, let's analyze each answer choice:

A) A student who is not in the top sixty percent of the class is not successful.
This assumption is not necessary for the teacher's conclusion. The categorization of students into three groups does not imply that those outside the top sixty percent are automatically unsuccessful. The teacher's conclusion is about "most" of his students being successful, not about the success or failure of individual students.

B) Students in this teacher's class are more likely to be successful than are most other students.
This assumption is not necessary for the teacher's conclusion. The comparison of success rates between the teacher's class and other classes is not relevant to the conclusion that most of the teacher's students are successful.

C) Students in classes in which only the top thirty percent are categorized as successful are more likely to succeed in a non-academic setting than are students in this teacher's class.
This assumption is not necessary for the teacher's conclusion. The comparison between academic and non-academic success rates is not addressed in the argument, and it does not impact the conclusion that most of the teacher's students are successful.

D) Students are more likely to be successful than unsuccessful.
This assumption is not necessary for the teacher's conclusion. It is a general statement that does not provide any specific information about the students in the teacher's class or their categorization.

E) It is possible to categorize students accurately as being successful, borderline successful, or unsuccessful.
This assumption is necessary for the teacher's conclusion to be logically correct. If it is not possible to accurately categorize students into the three groups, then the teacher's conclusion based on those categories would not be valid.

Therefore, the necessary assumption for the teacher's conclusion to be logically correct is (E) It is possible to categorize students accurately as being successful, borderline successful, or unsuccessful.

To identify the assumption made by the personnel director, let's analyze each answer choice:

A. No other performance rating system is as good as the current system.
This assumption is not necessary for the personnel director's conclusion. The satisfaction of employees with the current system does not necessarily depend on the comparison with other systems. The conclusion is specifically about the relationship between high-rated employees and their satisfaction with the current system, rather than a comparison with alternative systems.

B. The company's best-performing employees received high ratings.
This assumption is necessary for the personnel director's conclusion. If the best-performing employees did not receive high ratings, then the correlation between high ratings and satisfaction with the system would not hold, and the conclusion that the company's best-performing employees liked the system would be undermined.

C. Employees who received low ratings were dissatisfied with the system.
This assumption is not necessary for the personnel director's conclusion. The conclusion is about the satisfaction of high-rated employees, not the dissatisfaction of low-rated employees. The data from the survey only address the satisfaction of high-rated employees, and the conclusion does not depend on the satisfaction levels of low-rated employees.

D. Employees who receive high ratings from a performance-rating system will like that system.
This assumption is not necessary for the personnel director's conclusion. The conclusion is specifically about the satisfaction of employees who received high ratings, but it does not make a general claim that all employees who receive high ratings will like the system. The conclusion is based on the observed correlation in the survey data, rather than a universal statement about high-rated employees.

E. The company's best-performing employees were motivated to perform well by the knowledge that they would receive performance ratings.
This assumption is not necessary for the personnel director's conclusion. The conclusion is about the satisfaction of the best-performing employees, not the specific motivation behind their performance. The survey data focus on the satisfaction of high-rated employees, but it does not explicitly link their motivation to their performance ratings.

Therefore, the correct assumption for the personnel director's conclusion is (B) The company's best-performing employees received high ratings.

To identify the assumption made in the argument, let's analyze each answer choice:

(A) All of the applicants were very well qualified for a job at either Evco or Radeco.
This assumption is not necessary for the argument. The argument does not rely on the qualification level of the applicants but rather on the fact that all applicants were offered a job.

(B) All of the applicants accepted a job at either Evco or Radeco.
This assumption is not necessary for the argument. The argument is focused on the fact that both Evco and Radeco offered jobs to half of the applicants, not on whether all the applicants accepted the job offers.

(C) None of the applicants was offered a job by both Evco and Radeco.
This assumption is necessary for the argument. The argument assumes that each applicant received a job offer from only one company. If any applicant had received job offers from both Evco and Radeco, it would undermine the conclusion that every applicant must have been offered a job.

(D) None of the applicants had applied for jobs at places other than Evco and Radeco.
This assumption is not necessary for the argument. The argument does not make any claims about the applicants' applications to places other than Evco and Radeco.

(E) None of the applicants had previously worked for either Evco or Radeco.
This assumption is not necessary for the argument. The argument does not depend on whether the applicants had prior work experience with either Evco or Radeco.

Therefore, the correct assumption for the argument is (C) None of the applicants was offered a job by both Evco and Radeco.

To identify the assumption made in the argument, let's analyze each answer choice:

A) There are more murders per year in the United States than in the Philippines.
This assumption is not necessary for the argument. The argument does not rely on the comparison of murder rates between the United States and the Philippines. It focuses on the legal status of the death penalty and the majority belief in each country.

B) The legal status of capital punishment in the United States and the Philippines aligns with how the majority of citizens in those respective countries view the death penalty.
This assumption is necessary for the argument. The argument is based on the difference in the legality of capital punishment between the two countries, and it assumes that the legal status reflects the majority belief. If the legal status did not align with the majority view, then the argument's conclusion about the beliefs of American and Filipino citizens would be undermined.

C) There are not strong voices opposing the death penalty in the United States.
This assumption is not necessary for the argument. The argument focuses on the majority belief, not on the presence or strength of voices opposing the death penalty. The argument does not make any claims about the presence or absence of opposition to the death penalty in the United States.

D) Most American citizens who believe in the death penalty think that it acts as a deterrent for potential criminals, while most Filipino citizens do not.
This assumption is not necessary for the argument. The argument does not depend on the reasons behind the majority belief in each country. It focuses on the legal status of capital punishment and its relationship to the majority belief, rather than the specific beliefs about deterrence.

E) The legal standard used to determine whether a criminal should be sentenced to the death penalty in the United States is similar to the legal standard used in the Philippines before capital punishment was abolished there.
This assumption is not necessary for the argument. The argument is not concerned with the legal standards used in each country, but rather with the difference in the legality of the death penalty and its implication for the majority belief.

Therefore, the correct assumption for the argument is (B) The legal status of capital punishment in the United States and the Philippines aligns with how the majority of citizens in those respective countries view the death penalty.

A. Serious scientific research is not a solitary activity, but relies on active cooperation among a group of colleagues.
This option discusses the collaborative nature of scientific research, but it doesn't directly relate to the assumption about documentary nature films and the loss of colleague status.

B. Research scientists tend not to regard as colleagues those scientists whose renown they envy.
While envy could be a factor in some cases, the assumption made in the explanation does not explicitly mention envy as the reason for the loss of colleague status.

C. A scientist can become famous as a marine biologist who makes documentary films without having completed any important research.
This option aligns with the assumption presented in the explanation. If a scientist gains fame solely through documentary films without contributing to important research, other scientists may question their dedication to scientific research.

D. Research scientists believe that those who are well known as marine biologists who make documentary films are not motivated to do important new research.
This option also captures the assumption made in the explanation. If research scientists believe that those who become well-known for making documentary films lack motivation to do important new research, it would contribute to their diminished colleague status.

E. No important new research can be accessible to or accurately assessed by those who are not themselves scientists.
While this option addresses the accessibility and assessment of research by non-scientists, it does not directly address the assumption related to marine biologists who make documentary films losing their colleague status.

Considering the above analysis, the assumption that aligns with the explanation is:

D. Research scientists believe that those who are well known as marine biologists who make documentary films are not motivated to do important new research.

(A) Comets tend to be composed largely of ice while asteroids are composed mainly of rock.
This option provides general information about the composition of comets and asteroids, but it does not directly support the conclusion drawn in the argument.

(B) If Jupiter’s lower atmosphere had been penetrated by the comet’s fragments, the resulting formations would show signs of water.
This assumption aligns with the argument's conclusion. It suggests that the absence of water in the formations indicates that the comet's fragments did not penetrate Jupiter's lower atmosphere.

(C) A larger explosion would occur upon collision with Jupiter if Shoemaker-Levy 9 were composed of rock than if it were composed of ice.
This option introduces a comparison between the explosion caused by rock and ice compositions, but it does not directly address the assumption made in the argument.

(D) The post-collision analysis of Jupiter showed that the formations all had exactly the same composition.
This option, if assumed, would support the conclusion that the comet was composed of rock rather than ice. However, the passage does not provide information regarding the post-collision analysis of Jupiter's formations.

(E) The deeper the explosion occurred in Jupiter’s atmosphere, the more difficult it would be to detect from Earth.
While this option introduces a relationship between the depth of the explosion and its detectability from Earth, it does not address the assumption made in the argument.

Based on the analysis, the assumption on which the argument depends is:

(B) If Jupiter’s lower atmosphere had been penetrated by the comet’s fragments, the resulting formations would show signs of water.