GWD3-40

evelyn205205

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 brain 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 assumptionon which the reasoning in the argument above depends?

1. No part of a person’s brain that is damaged by a stroke ever recovers.
   
2. Impairment of linguistic capabilities does not occur in people who have not suffered any damage to any language center of the brain.
   
3. Strokes tend to impair linguistic capabilities more severely than does any other cause of damage to language centers in the brain.
   
4. 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.
   
5. 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.
   
   ANSWER: D
   想请教各位大侠，这段话怎么理解呢？
   

evelyn205205

期待各位大侠咯，谢谢哦

sdcar2010

To find a necessary assumption, use negation.

If you negate D, then you get : if there are language centers on the left side of the brain, any serious stroke affecting that side of the brain DOES NOT damage at least one of them. If that is the case, the conclusion is wrong because people who suffer strokes on the left but still can talk could have language centers on the left side.

evelyn205205

也就是说at least one of them里面的them是指language centers咯？

evelyn205205

还不是很懂。。。