GWD-13-40,又是一道莫逆两可

B也应该说得过去亚，那为什么就是D呢？

For most people, the left half of the brain controls linguistic capabilities, but some people have their language centers in the right half. When a language center of the brains is damaged, for example, by a stroke, linguistic capabilities are impaired in some way. Therefore, people who have suffered a serious stroke on the left side of the brain without suffering any such impairment must have their language centers in the right half.

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

A.      No part of a person’s brain that is damaged by a stroke never recovers

B.      Impairment of linguistic capabilities does not occur in people who have not suffered any damage to any language center of the brain.

C.      Strokes tend to impair linguistic capabilities more severely than does any other cause of damage to language centers in the brain.

D.      If there are language centers on the left side of the brain, any serious stroke affecting that side of the brain damages at least one of them.

E.      It is impossible to determine which side of the brain contains a person’s language centers if the person has not suffered damage to either side of the brain.

没有颠倒因果吧，Impairment of linguistic capabilities does not occur in people who have not suffered any damage to any language center of the brain

意思说语言功能没有受影响的的人的脑部语言中枢一定没有受到损伤，是一个必然的关系，

那么如果如果左脑遭到重击，语言功能受到影响，相应的语言中枢一定在左脑，如果语言功能不受影响，相应的语言中枢没有受损，那么一定在右脑

B在自说自话。结论强调的是受到stroke以后左右脑的区别，与没有受到stroke之前无关。

把B取非，对结论无任何影响