Critical Reasoning

A study of high blood pressure treatments found that certain meditation techniques and the most commonly prescribed drugs are equally effective if the selected treatment is followed as directed over the long term. Half the patients given drugs soon stop taking them regularly, whereas eighty percent of the study's participants who were taught meditation techniques were still regularly using them five years later. Therefore, the meditation treatment is the one likely to produce the best results. B The participants in the study were selected in part on the basis of their willingness to use meditation techniques. C Meditation techniques can reduce the blood pressure of people who do not suffer from high blood pressure. D Some of the participants in the study whose high blood pressure was controlled through meditation techniques were physicians. E Many people with dangerously high blood pressure are unaware of their condition.

Duckbill dinosaurs, like today's monitor lizards, had particularly long tails, which they could whip at considerable speed. Monitor lizards use their tails to strike predators. However, although duckbill tails were otherwise very similar to those of monitor lizards, the duckbill's tailbones were proportionately much thinner and thus more delicate. Moreover, to ward off their proportionately much larger predators, duckbills would have had to whip their tails considerably faster than monitor lizards do. The information given, if accurate, provides the strongest support for which of the following hypotheses?

Highway Official: When resurfacing our concrete bridges, we should use electrically conductive concrete (ECC) rather than standard concrete. In the winter, ECC can be heated by passing an electric current through it, thereby preventing ice buildup. The cost of the electricity needed is substantially lower than the cost of the de-icing salt we currently use. Taxpayer: But construction costs for ECC are much higher than for standard concrete, so your proposal is probably not justifiable on economic grounds. Which of the following, if true, could best be used to support the highway official�s proposal in the face of taxpayer�s objection?

Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack. Which of the following, if true, most seriously calls into question the explanation given for the thrush�s diet during migration?

Biologists with a predilection for theory have tried�and largely failed�to define what it is that makes something a living thing. Organisms take in energy-providing materials and excrete waste products, but so do automobiles. Living things replicate and take part in evolution, but so do some computer programs. We must be open to the possibility that there are living things on other planets. Therefore, we will not be successful in defining what it is that makes something a living thing merely by examining living things on Earth�the only ones we know. Trying to do so is analogous to trying to specify _______. Which of the following most logically completes the passage?

Ramirez: The film industry claims that pirated DVDs, which are usually cheaper than legitimate DVDs and become available well before a film's official DVD release date, adversely affect its bottom line. But the industry should note what the spread of piracy indicates: consumers want lower prices and faster DVD releases. Lowering prices of DVDs and releasing them sooner would mitigate piracy's negative effect on film industry profits. The argument above relies on which of the following assumptions?

Film Director: It is true that certain characters and plot twists in my newly released film The Big Heist are strikingly similar to characters and plot twists in Thieves, a movie that came out last year. Based on these similarities, the film studio that produced Thieves is now accusing me of taking ideas from that film. The accusation is clearly without merit. All production work on The Big Heist was actually completed months before Thieves was released. Which of the following, if true, provides the strongest support for the director's rejection of the accusation?

That the application of new technology can increase the productivity of existing coal mines is demonstrated by the case of Tribnia's coal industry. Coal output per miner in Tribnia is double what it was five years ago, even though no new mines have opened. Which of the following can be properly concluded from the statement about coal output per miner in the passage?

Delta Products Inc. has recently switched at least partly from older technologies using fossil fuels to new technologies powered by electricity. The question has been raised whether it can be concluded that for a given level of output Delta's operation now causes less fossil fuel to be consumed than it did formerly. The answer, clearly, is yes, since the amount of fossil fuel used to generate the electricity needed to power the new technologies is less than the amount needed to power the older technologies, provided level of output is held constant In the argument given, the two boldfaced portions play which of the following roles?

In Mernia commercial fossil hunters often sell important fossils they have found, not to universities or museums, but to individual collectors, who pay much better but generally do not allow researchers access to their collections. To increase the number of fossils available for research, some legislators propose requiring all fossils that are found in Merina to be sold only to universities or museums. Which of the following, if true, most strongly indicates that the legislators' proposal will fail to achieve its goal?

Paper and plastic grocery bags are a continuing problem for the city, both as litter and in landfills. To discourage their use, the city council has proposed a tax on each bag, to be paid by the supermarkets that supply them. Several environmental groups, however, oppose the tax, despite having brought the issue to the council�s attention in the first place. Which of the following, if true, would best explain the environmental groups� opposition to the proposed tax?

Source : GMATPrep Default Exam Pack Which of the following most logically completes the argument?

A group of children of various ages was read stories in which people caused harm, some of those people doing so intentionally, and some accidentally. When asked about appropriate punishments for those who had caused harm, the younger children, unlike the older ones, assigned punishments that did not vary according to whether the harm was done intentionally or accidentally. Younger children, then, do not regard people's intentions as relevant to punishment. B In these stories, the severity of the harm produced was clearly stated. C Younger children are as likely to produce harm unintentionally as are older children. D The older children assigned punishment in a way that closely resembled the way adults had assigned punishment in a similar experiment. E The younger children assigned punishments that varied according to the severity of the harm done by the agents in the stories.

In Wareland last year, 16 percent of licensed drivers under 21 and 11 percent of drivers ages 21-24 were in serious accidents. By contrast, only 3 percent of licensed drivers 65 and older were involved in serious accidents. These figures clearly show that the greater experience and developed habits of caution possessed by drivers in the 65-and-older group make them far safer behind the wheel than the younger drivers are. Which of the following is an assumption on which the argument depends?

Manufacturing plants in Arundia have recently been acquired in substantial numbers by investors from abroad. Arundian politicians are proposing legislative action to stop such investment, justifying the proposal by arguing that foreign investors, opportunistically exploiting a recent fall in the value of the Arundian currency, were able to buy Arundian assets at less than their true value. Which of the following, if true, casts the most serious doubt on the adequacy of the Arundian politicians' justification for the proposed legislation?

Source : GMATPrep Default Exam Pack One of the limiting factors in human physical performance is the amount of oxygen that is absorbed by the muscles from the bloodstream. Accordingly, entrepreneurs have begun selling at gymnasiums and health clubs bottles of drinking water, labeled "SuperOXY," that has extra oxygen dissolved in the water. Such water would be useless in improving physical performance, however, since the amount of oxygen in the blood of people who are exercising is already more than the muscle can absorb. Which of the following, if true, would serve the same function in the argument as the statement in boldface?

Twelve years ago and again five years ago, there were extended periods when the Darfir Republic's currency, the pundra, was weak: its value was unusually low relative to the world's most stable currencies. Both times a weak pundra made Darfir's manufactured products a bargain on world markets, and Darfir's exports were up substantially. Now some politicians are saying that, in order to cause another similarly sized increase in exports, the government should allow the pundra to become weak again. Which of the following, if true, provides the government with the strongest grounds to doubt that the politicians' recommendation, if followed, will achieve its aim?

Farmer: Worldwide, just three grain crops�rice, wheat, and corn�account for most human caloric intake. To maintain this level of caloric intake and also keep pace with global population growth, yields per acre from each of these crops will have to increase at least 1.5 percent every year, given that the supply of cultivated land is diminishing. Therefore, the government should increase funding for research into new ways to improve yields. Which of the following is an assumption on which the farmer's argument depends?

In persons with astigmatism, the clear outer layer of the eye is deformed in a way that impairs and sometimes distorts vision. The elongated figures in the paintings of El Greco (1541�1614) were so unusual that some critics sought to explain them by hypothesizing that, without knowing it, El Greco had an astigmatism that caused everything to appear to him in the distorted way that was characteristic of his painted figures. The proposed explanation is most vulnerable to the criticism that it fails to

Thyrian lawmaker: Thyria�s Cheese Importation Board inspects all cheese shipments to Thyria and rejects shipments not meeting specified standards. Yet only 1 percent is ever rejected. Therefore, since the health consequences and associated economic costs of not rejecting that 1 percent are negligible, whereas the board�s operating costs are considerable, for economic reasons alone the board should be disbanded. Consultant: I disagree. The threat of having their shipments rejected deters many cheese exporters from shipping substandard product. The consultant responds to the lawmaker�s argument by