1. 加强题(GWD6-Q15) Capuchin monkeys often rub their bodies with a certain type of millipede. Laboratory tests show that secretions from the bodies of these millipedes are rich in two chemicals that are potent mosquito repellents, and mosquitoes carry parasites that debilitate capuchins. Some scientists hypothesize that the monkeys rub their bodies with the millipedes because doing so helps protect them from mosquitoes. Which of the following, if true, provides the most support for the scientists’ hypothesis? A. A single millipede often gets passed around among several capuchins, all of whom rub their bodies with it. B. The two chemicals that repel mosquitoes also repel several other varieties of insects. C. The capuchins rarely rub their bodies with the millipedes except during the rainy season, when mosquito populations are at their peak. D. Although the capuchins eat several species of insects, they do not eat the type of millipede they use to rub their bodies. E. The two insect-repelling chemicals in the secretions of the millipedes are carcinogenic for humans but do not appear to be carcinogenic for capuchins. 答案C。B选项容易造成干扰。选项B提到的“还能驱赶其他的虫子”属于扩大范围选项，无关。
2. 削弱题 (Prep44) In countries in which new life-sustaining drugs cannot be patented, such drugs are sold at widely affordable prices; those same drugs, where patented, command premium prices because the patents shield patent-holding manufacturers from competitors. These facts show that future access to new life-sustaining drugs can be improved if the practice of granting patents on newly developed life-sustaining drugs were to be abolished everywhere. Which of the following, if true, most seriously weakens the argument? (A) In countries in which life-sustaining drugs cannot be patented, their manufacture is nevertheless a profitable enterprise. (B) Countries that do not currently grant patents on life-sustaining drugs are, for the most part, countries with large populations. (C) In some countries specific processes for the manufacture of pharmaceutical drugs can be patented even in cases in which the drugs themselves cannot be patented. (D) Pharmaceutical companies can afford the research that goes into the development of new drugs only if patents allow them to earn high profits. (E) Countries that grant patents on life-sustaining drugs almost always ban their importation from countries that do not grant such patents. 答案D。C选项容易误选。C选项中有明显的缩小范围的关键词some，无关排出。