1. With the passage of the new tax reform laws, the annual tax burden on low-income taxpayers will be reduced, on average, by anywhere from $100 to $300. Clearly, tax reform is in the interest of low-income taxpayers.

Which one of the following, if true, most undermines the conclusion above?

2. If we are to expand the exploration of our solar system, our next manned flight should be to Phobos, one of Mars’s moons, rather than to Mars itself. The flight times to each are the same, but the Phobos expedition would require less than half the fuel load of a Mars expedition and would, therefore, be much less costly. So, it is clear that Phobos should be our next step in space exploration.

Which one of the following, if true, would most help to explain the difference in fuel requirements?

3. Scientific research that involves international collaboration has produced papers of greater influence, as measured by the number of times a paper is cited in subsequent papers, than has research without any collaboration. Papers that result from international collaboration are cited an average of seven times, whereas papers with single authors are cited only three times on average. This difference shows that research projects conducted by international research teams are of greater importance than those conducted by single researchers.

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

4. It is more desirable to have some form of socialized medicine than a system of medical care relying on the private sector. Socialized medicine is more broadly accessible than is a private-sector system. In addition, since countries with socialized medicine have a lower infant mortality rate than do countries with a system relying entirely on the private sector, socialized medicine seems to be technologically superior.

Which one of the following best indicates a flaw in the argument about the technological superiority of socialized medicine?

5. Most parents who are generous are good parents, but some self-centered parents are also good parents. Yet all good parents share one characteristic: they are good listeners.

If all of the statements in the passage are true, which one of the following must also be true?

6. Lourdes: Dietary fiber is an important part of a healthful diet. Experts recommend that adults consume 20 to 35 grams of fiber a day. Kyra: But a daily intake of fiber that is significantly above that recommended level interferes with mineral absorption, especially the absorption of calcium. The public should be told to cut back on fiber intake.

Which one of the following, if true, most undermines Kyra’s recommendation?

7. A certain retailer promotes merchandise by using the following policy: At all times there is either a “manager’s sale” or a “holiday sale” or both going on. All sales are run for exactly one calendar month. In any given month, if a manager wishes to clear out a particular line of merchandise, then a manager’s sale is declared. If a holiday falls within the calendar month and there is excess merchandise in the warehouse, then a holiday sale is declared. However, there is no holiday that falls within the month of August and, in that month, the warehouse never contains excess merchandise.

Which one of the following can be concluded from the passage?

8. Prominent business executives often play active roles in United States presidential campaigns as fund-raisers or backroom strategists, but few actually seek to become president themselves. Throughout history the great majority of those who have sought to become president have been lawyers, military leaders, or full-time politicians. This is understandable, for the personality and skills that make for success in business do not make for success in politics. Business is largely hierarchical, whereas politics is coordinative. As a result, business executives tend to be uncomfortable with compromises and power-sharing, which are inherent in politics.

Which one of the following, if true, most seriously weakens the proposed explanation of why business executives do not run for president?

9. A scientific theory is a good theory if it satisfies two requirements: It must accurately describe a large class of observations in terms of a model that is simple enough to contain only a few elements, and it must make definite predictions about the results of future observations. For example, Aristotle’s cosmological theory, which claimed that everything was made out of four elements—earth, air, fire, and water—satisfied the first requirement, but it did not make any definite predictions. Thus, Aristotle’s cosmological theory was not a good theory.

If all the statements in the passage are true, each of the following must also be true EXCEPT:

10. Millions of irreplaceable exhibits in natural history museums are currently allowed to decay. Yet without analyses of eggs from museums, the studies linking pesticides with the decline of birds of prey would have been impossible. Therefore, funds must be raised to preserve at least those exhibits that will be most valuable to science in the future.

The argument presupposes that

11. Compared to nonprofit hospitals of the same size, investor-owned hospitals require less public investment in the form of tax breaks, use fewer employees, and have higher occupancy levels. It can therefore be concluded that investor-owned hospitals are a better way of delivering medical care than are nonprofit hospitals.

Which one of the following, if true, most undermines the conclusion drawn above?

12. The ancient Egyptian pharaoh Akhenaten, who had a profound effect during his lifetime on Egyptian art and religion, was well loved and highly respected by his subjects. We know this from the fierce loyalty shown to him by his palace guards, as documented in reports written during Akhenaten’s reign.

A questionable technique used in the argument is to

13. Physician: The patient is suffering either from disease X or else from disease Y, but there is no available test for distinguishing X from Y. Therefore, since there is an effective treatment for Y but no treatment for X, we must act on the assumption that the patient has a case of Y.

The physician’s reasoning could be based on which one of the following principles?

14. Consumer advocate: Tropical oils are high in saturated fats, which increase the risk of heart disease. Fortunately, in most prepared food tropical oils can be replaced by healthier alternatives without noticeably affecting taste. Therefore, intensive publicity about the disadvantage of tropical oils will be likely to result in dietary changes that will diminish many people’s risk of developing heart disease. Nutritionist: The major sources of saturated fat in the average North American diet are meat, poultry, and dairy products, not tropical oils. Thus, focusing attention on the health hazards of tropical oils would be counterproductive, because it would encourage people to believe that more substantial dietary changes are unnecessary.

Which one of the following is a point at issue between the nutritionist and the consumer advocate?

15. People who take what others regard as a ridiculous position should not bother to say, “I mean every word!” For either their position truly is ridiculous, in which case insisting that they are serious about it only exposes them to deeper embarrassment, or else their position has merit, in which case they should meet disbelief with rational argument rather than with assurances of their sincerity.

Which one of the following arguments is most similar in its reasoning to the argument above?

16. Concetta: Franchot was a great writer because she was ahead of her time in understanding that industrialization was taking an unconscionable toll on the family structure of the working class. Alicia: Franchot was not a great writer. The mark of a great writer is the ability to move people with the power of the written word, not the ability to be among the first to grasp a social issue. Besides, the social consequences of industrialization were widely understood in Franchot’s day.

In her disagreement with Concetta, Alicia does which one of the followings?

17. Zeida: Dr. Ladlow, a research psychologist, has convincingly demonstrated that his theory about the determinants of rat behavior generates consistently accurate predictions about how rats will perform in a maze. On the basis of this evidence, Dr. Ladlow has claimed that his theory is irrefutably correct. Anson: Then Dr. Ladlow is not a responsible psychologist. Dr. Ladlow’s evidence does not conclusively prove that his theory is correct. Responsible psychologists always accept the possibility that new evidence will show that their theories are incorrect.

Which one of the following can be properly inferred from Anson’s argument?

18. Zeida: Dr. Ladlow, a research psychologist, has convincingly demonstrated that his theory about the determinants of rat behavior generates consistently accurate predictions about how rats will perform in a maze. On the basis of this evidence, Dr. Ladlow has claimed that his theory is irrefutably correct. Anson: Then Dr. Ladlow is not a responsible psychologist. Dr. Ladlow’s evidence does not conclusively prove that his theory is correct. Responsible psychologists always accept the possibility that new evidence will show that their theories are incorrect. Anson bases his conclusion about Dr.

Ladlow on which one of the following?

19. Smith: Meat in the diet is healthy, despite what some people say.

After all, most doctors do eat meat, and who knows more about health than doctors do? Which one of the following is a flaw in Smith’s reasoning?

20. The rise in the prosperity of England subsequent to 1840 can be attributed to the adoption of the policy of free trade, since economic conditions improved only when that policy had been implemented.

The reasoning in the above argument most closely parallels that in which one of the following?

21. During construction of the Quebec Bridge in 1907, the bridge’s designer, Theodore Cooper, received word that the suspended span being built out from the bridge’s cantilever was deflecting downward by a fraction of an inch. Before he could telegraph to freeze the project, the whole cantilever arm broke off and plunged, along with seven dozen workers, into the St. Lawrence River. It was the worst bridge construction disaster in history. As a direct result of the inquiry that followed, the engineering “rules of thumb” by which thousands of bridges had been built went down with the Quebec Bridge. Twentieth-century bridge engineers would thereafter depend on far more rigorous applications of mathematical analysis.

Which one of the following statements can be properly inferred from the passage?

22. Most children find it very difficult to explain exactly what the words they use mean when those words do not refer to things that can be seen or touched. Yet, since children are able to use these words to convey the feelings and emotions they are obviously experiencing, understanding what a word means clearly does not depend on being able to explain it.

Which one of the following principles, if accepted, would provide the most justification for the conclusion?

23. The brains of identical twins are genetically identical. When only one of a pair of identical twins is a schizophrenic, certain areas of the affected twin’s brain are smaller than corresponding areas in the brain of the unaffected twin. No such differences are found when neither twin is schizophrenic. Therefore, this discovery provides definitive evidence that schizophrenia is caused by damage to the physical structure of the brain.

Which one of the following is an assumption required by the argument?

24. The brains of identical twins are genetically identical. When only one of a pair of identical twins is a schizophrenic, certain areas of the affected twin’s brain are smaller than corresponding areas in the brain of the unaffected twin. No such differences are found when neither twin is schizophrenic. Therefore, this discovery provides definitive evidence that schizophrenia is caused by damage to the physical structure of the brain.

If the statements on which the conclusion above is based are all true, each of the following could be true EXCEPT:

25. Sixty adults were asked to keep a diary of their meals, including what they consumed, when, and in the company of how many people. It was found that at meals with which they drank alcoholic beverages, they consumed about 175 calories more from nonalcoholic sources than they did at meals with which they did not drink alcoholic beverages. Each of the following, if true, contributes to an explanation of the difference in caloric intake EXCEPT: