A study examining ninety large cities found that in those with more kilometers of bicycle paths and roadway bicycle lanes per capita, higher percentages of the population commute to work by bicycle. For this reason the study concluded that adding bicycle paths and lanes is an effective way to encourage commuters to bicycle rather than drive.

Which of the following, if true, would most weaken the reasoning in the study’

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Members of many primate species approach an opponent shortly after conflict and initiate behaviors such as embracing, grooming, or huddling―a phenomenon researchers call postconflict reconciliation. Existing research, however, suffers from several shortcomings. The variability between groups of the same species is rarely addressed; the majority of studies investigate only a small fraction of the pairings that exist in a given group; and almost all reports are restricted to animals in captivity.

In an attempt to address some of these shortcomings, Sommer et al. recently conducted a study of postconflict reconciliation in wild Hanuman langurs, a species of colobine monkey. They observed rates of postconflict reconciliation much lower than would be expected based on previous research, and found that over 80 percent of all pairings exhibited no postconflict affinity whatsoever. The rarity of friendly postconflict reunion in wild langurs draws attention to the possibility that conflicts are modulated through avoidance. The option of temporarily avoiding contact with opponents is not easily available to captive primates, and certainly not to the extent present in the wild. Still, studies of postconflict behavior of primates in captivity remain valuable: above all, they demonstrate the flexibility of nonhuman primates in various environments. It is likely, however, that the reported frequency of reconciliation among primates is artificially inflated by the conditions of captivity.

The passage suggests that one reason that the "conditions of captivity" (see bolded text) were significant was that

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It can be inferred from the passage that if Cope’s hypothesis were correct, which of the following would most likely be true concerning salt-affected areas in Victoria?

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Excavation in City Y found ten ships that all sank at the same time in the city’s harbor, in one sudden event in approximately A.D. 800. One possible explanation for the sinking is a tsunami, caused by a strong earthquake from a fault under the sea about fifteen miles away. However, it is more likely that a powerful storm sank the ships, since, if an earthquake had been responsible, there would also have been major damage to the city’s walls and buildings―but there apparently was no such major damage, otherwise we would have discovered records from that time mentioning major building repairs.

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

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Although a village in a drouqht-stncken area may at first be resistant to using new agricultural techniques, if the village leaders are consulted beforehand and the benefits of the techniques are demonstrated clearly, the agricultural ministry can often effect a real and positive change in agricultural productivity and thus in economic security.

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When new regulations were imposed on businesses selling in the same markets as Acme Inc. and the demographics began to change unfavorably for its main product: there was very little that it could have done different in the short term.

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The real estate company pleaded guilty in a district court in failing to report all of the profits from the sale of land for the new shopping mall.

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For the first time, prospectors have laid claim to rich deposits of gold, silver, and copper in the deep sea, foreshadowing a possible rush to the open oceans for metals and a possible fight with conservationists over exploitation of the sea’s dark recesses.

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Parasitic wasps propagate by injecting their eggs into a caterpillar that then becomes paralyzed as the eggs inside develop into wasp larvae. The wasp larvae kill the caterpillar host as they feed on it, form cocoons, and finally develop into wasps. In attempting to discover how such wasps detect the presence of the caterpillar hosts that are so critical to the wasps’ propagation, researchers have uncovered an intriguing defense mechanism developed by the plants on which the caterpillars feed.

When chewed on, many plants release volatile compounds from both damaged and undamaged tissues. When these compounds are toxic to the insects that feed on the plants, they can help defend the plants from such attacks. However, the plants on which the wasps’ caterpillar hosts feed have evolved an even more complex defense: the caterpillar-infested plants appear to release volatile chemicals that attract parasitic wasps, which then prey on the caterpillars. Scientists originally suspected that the wasps were attracted by an odor, reminiscent of cut grass, that is released as the caterpillar feeds, but a recent study suggests that a different set of volatile attractants is involved. In this study,

when researchers used a razor blade to mimic caterpillar damage on the leaves, only grassy odors were emitted, not the volatile compounds that attracted wasps. However, when oral secretions from the caterpillars were applied to these damaged leaves, the leaves released the wasp attractants several hours later. Further tests revealed that oral secretions placed on the razor-damaged leaves stimulated the release of such attractants, making the plants as attractive to wasps as plants that had suffered actual caterpillar damage. These results suggest that chemicals from the caterpillar must be present for these attractants to be released and that unlike the grassy scent, which emanates only as the caterpillar on the plant, the wasp attractants are produced several hours after the attack and persist for several hours, perhaps days. Researchers have launched additional studies to determine whether the wasps’ capacity to prey on caterpillars can be enhanced to the extent that the wasps could be used as a natural pesticide to "police" plants and protect them from crop-destroying caterpillars.

The passage is primarily concerned with doing which of the following?

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Parasitic wasps propagate by injecting their eggs into a caterpillar that then becomes paralyzed as the eggs inside develop into wasp larvae. The wasp larvae kill the caterpillar host as they feed on it, form cocoons, and finally develop into wasps. In attempting to discover how such wasps detect the presence of the caterpillar hosts that are so critical to the wasps’ propagation, researchers have uncovered an intriguing defense mechanism developed by the plants on which the caterpillars feed.

When chewed on, many plants release volatile compounds from both damaged and undamaged tissues. When these compounds are toxic to the insects that feed on the plants, they can help defend the plants from such attacks. However, the plants on which the wasps’ caterpillar hosts feed have evolved an even more complex defense: the caterpillar-infested plants appear to release volatile chemicals that attract parasitic wasps, which then prey on the caterpillars. Scientists originally suspected that the wasps were attracted by an odor, reminiscent of cut grass, that is released as the caterpillar feeds, but a recent study suggests that a different set of volatile attractants is involved. In this study, when researchers used a razor blade to mimic caterpillar damage on the leaves, only grassy odors were emitted, not the volatile compounds that attracted wasps. However, when oral secretions from the caterpillars were applied to these damaged leaves, the leaves released the wasp attractants several hours later. Further tests revealed that oral secretions placed on the razor-damaged leaves stimulated the release of such attractants, making the plants as attractive to wasps as plants that had suffered actual caterpillar damage. These results suggest that chemicals from the caterpillar must be present for these attractants to be released and that unlike the grassy scent, which emanates only as the caterpillar on the plant, the wasp attractants are produced several hours after the attack and persist for several hours, perhaps days. Researchers have launched additional studies to determine whether the wasps’ capacity to prey on caterpillars can be enhanced to the extent that the wasps could be used as a natural pesticide to "police" plants and protect them from crop-destroying caterpillars.

The first two sentences of the second paragraph serve primarily to

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