请教一道OG的题目！

alexousvi

106. Exposure to certain chemicals commonly used in elementary schools as cleaners or pesticides causes allergic reactions in some children. Elementary school nurses in Renston report that the proportion of schoolchildren sent to them for treatment of allergic reactions to those chemicals has increased
significantly over the past ten years. Therefore, either Renston’s schoolchildren have been exposed to greater quantities of the chemicals, or they are more sensitive to them than schoolchildren were ten years ago.

Which of the following is an assumption on which the argument depends?
(A) The number of school nurses employed by Renston’s elementary schools has not decreased over the past ten years.
(B) Children who are allergic to the chemicals are no more likely than other children to have allergies to other substances.
(C) Children who have allergic reactions to the chemicals are not more likely to be sent to a school nurse now than they were ten years ago.
(D) The chemicals are not commonly used as cleaners or pesticides in houses and apartment buildings in Renston.
(E) Children attending elementary school do not make up a larger proportion of Renston’s population now than they did ten years ago.

我选了A，答案是C。

A选项，R地区小学所雇佣的护士的数量在过去10年没减少。取反的话，如果该地区小学雇佣护士的数量减少了，那每个人平均分配到的病人数量就会提升。他因导致变化，应该是正确的啊？另外，C选项，不送到学校护士那里去了，数量应该会减少吧？我哪里出错了吗？

brfmzbjz

本题想论证的是
exposure to greater quantities of chemicals or students being more sensitive
导致了
就诊的学生占比增多

要支持这个论证 (或者说提供assumption)
要么要加强本身的因果关系，要么要排除别的原因

C选项，要注意，是no more LIKELY to be sent, 也就是说不会因为【比方说老师家长更操心啦】而更倾向把学生送去护士那里【以前可能浑身起疹子才送去医院，现在可能手指发红就送去医院】。这就排除了一个别的造成去就诊学生占比提升的原因。

A 选项，你说的每个人平均分配到的病人数量提升，和题干里的“果”没有任何关系
题干是说就诊的学生占比提升了

alexousvi

brfmzbjz 发表于 2014-6-15 07:17
本题想论证的是
exposure to greater quantities of chemicals or students being more sensitive
导致了

原来如此，多谢解惑！