Philosopher: Graham argues that since a person is truly happy only when doing something, the best life is a life that is full of activity. But we should not be persuaded by Graham’s argument. People sleep, and at least sometimes when sleeping, they are truly happy, even though they are not doing anything.

Which one of the following most accurately describes the role played in the philosopher’s argument by the claim that at least sometimes when sleeping, people are truly happy, even though they are not doing anything?

Historian: In rebuttal of my claim that West influenced Stuart, some people point out that West’s work is mentioned only once in Stuart’s diaries. But Stuart’s diaries mention several meetings with West, and Stuart’s close friend, Abella, studied under West. Furthermore, Stuart’s work often uses West’s terminology which, though now commonplace, none of Stuart’s contemporaries used.

Which one of the following propositions is most supported by the historian’s statements, if those statements are true?

One theory to explain the sudden extinction of all dinosaurs points to “drug overdoses” as the cause. Angiosperms, a certain class of plants, first appeared at the time that dinosaurs became extinct. These plants produce amino-acid-based alkaloids that are psychoactive agents. Most plant-eating mammals avoid these potentially lethal poisons because they taste bitter. Moreover, mammals have livers that help detoxify such drugs. However, dinosaurs could neither taste the bitterness nor detoxify the substance once it was ingested. This theory receives its strongest support from the fact that it helps explain why so many dinosaur fossils are found in unusual and contorted positions.

Which one of the following, if true, would most undermine the theory presented above?

There are two ways to manage an existing transportation infrastructure: continuous maintenance at adequate levels, and periodic radical reconstruction. Continuous maintenance dispenses with the need for radical reconstruction, and radical reconstruction is necessitated by failing to perform continuous maintenance. Over the long run, continuous maintenance is far less expensive; nevertheless, it almost never happens.

Which one of the following, if true, most contributes to an explanation of why the first alternative mentioned is almost never adopted?

When a threat to life is common, as are automobile and industrial accidents, only unusual instances tend to be prominently reported by the news media. Instances of rare threats, such as product tampering, however, are seen as news by reporters and are universally reported in featured stories. People in general tend to estimate the risk of various threats by how frequently those threats come to their attention.

If the statements above are true, which one of the following is most strongly supported on the basis of them?

Most economists believe that reducing the price of any product generally stimulates demand for it. However, most wine merchants have found that reducing the price of domestic wines to make them more competitive with imported wines with which they were previously comparably priced is frequently followed by an increase in sales of those imported wines.

Which one of the following, if true, most helps to reconcile the belief of most economists with the consequences observed by most wine merchants?

Certain bacteria that produce hydrogen sulfide as a waste product would die if directly exposed to oxygen. The hydrogen sulfide reacts with oxygen, removing it and so preventing it from harming the bacteria. Furthermore, the hydrogen sulfide tends to kill other organisms in the area, thereby providing the bacteria with a source of food. As a result, a dense colony of these bacteria produces for itself an environment in which it can continue to thrive indefinitely.

Which one of the following is most strongly supported by the information above?

According to the theory of continental drift, in prehistoric times, many of today’s separate continents were part of a single huge landmass. As the plates on which this landmass rested began to move, the mass broke apart, and ocean water filled the newly created chasms. It is hypothesized, for example, that South America was once joined on its east coast with what is now the west coast of Africa.

Which one of the following discoveries, if it were made, would most support the above hypothesis about South America and Africa?

Several legislators claim that the public finds many current movies so violent as to be morally offensive. However, these legislators have misrepresented public opinion. In a survey conducted by a movie industry guild, only 17 percent of respondents thought that movies are overly violent, and only 3 percent found any recent movie morally offensive. These low percentages are telling, because the respondents see far more current movies than does the average moviegoer.

The reasoning in the argument is flawed in that the argument

In countries where government officials are neither selected by free elections nor open to criticism by a free press, the lives of citizens are controlled by policies they have had no role in creating. This is why such countries are prone to civil disorder, in spite of the veneer of calm such countries often present to a visitor. When people do not understand the purpose of the restrictions placed on their behavior they have a greater tendency to engage in civil disorder as an expression of their frustration.

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

Researcher: Hard water contains more calcium and magnesium than soft water contains. Thus, those who drink mostly soft water incur an increased risk of heart disease, stroke, and hypertension, for people being treated for these conditions tend to have lower levels of magnesium in their blood.

Which one of the following, if true, most undermines the researcher’s argument?

Psychologist: We asked 100 entrepreneurs and 100 business managers to answer various questions and rate how confident they were that their responses were correct. While members of each group were overconfident, in general the entrepreneurs were much more so than the business managers. This indicates that people who are especially overconfident are more likely to attempt to start a business in spite of the enormous odds against success than people who are less confident.

Which one of the following, if true, lends the most support to the psychologist’s conclusion?