【求助】跪求高手1道逻辑题

11.   “If the forest continues to disappear at its present pace, the koala will approach extinction,” said the biologist.

“So all that is needed to save the koala is to stop deforestation,” said the politician.

Which one of the following statements is consistent with the biologist’s claim but not with the politician’s claim?

(A) Deforestation continues and the koala becomes extinct.

(B) Deforestation is stopped and the koala becomes extinct.

      (C) Reforestation begins and the koala survives.

(D) Deforestation is slowed and the koala survives.

(E) Deforestation is slowed and the koala approaches extinction.

答案B，我认为C对，大家帮忙分析一下为什么B对啊？？谢谢

This question is a good tricky one.

B---have to understand the question.

it is asking for biologist but against politicain, then we have to ask ourselves why? what do we can get out?

biologist attributes extinction to forest disappearing.

forest dispearing=deforest + natural causes + others

so he doesn't specifically point out which one is the realy cause.

politician certainly attributes extinction to deforest.

If we are for biologist but against politician, what will happen?

that means the real cause of extinction can be any reason rather than deforest, in other words, deforest is eliminated out of the real reason.

So in the answer, we have to find out the one which denotes that deforest is not the reason of extinction.

B---only when the deforest is not the real cause, then like B---if the deforest is stoped, it won't stop the extinction, because it's not the real cause, it won't affect the extinction.

我觉得这题考的仅仅是充分必要条件 disappear在这里等于deforest也无所谓 强调的只是结果

disapear --> exinction 的否命题 不disapear-->不exinction 未必成立 选B; C是对politician的加强

这题也可以这样理解:

biologist说的话是前提，politician的话是结论，题干要求对结论削弱 选B（有因无果）

我认为是

B:disappear（deforest）---extinction   P:只要stop deforest（deforest取非）---save（ectinction取非）

假设X是deforest，Y是extinction

那么生物学家的观点就是 X--Y，政治家的观点就是非X--非Y

问支持B 反对P，B选项说 Deforestation is stopped and the koala becomes extinct

简化之后就是 非X--Y，并不能推出一定支持生物学家，也并不能推出反对政治家

If the forest continues to disappear at its present pace, the koala will approach extinction.said the biologist.

首先感谢您的回答。但是从B中我只读出了deforest推出extinction，不知道这个forest dispearing=deforest + natural causes + others您如何推出的，而且这个和考拉熊的extiction有什么关系。麻烦您再解释一下，谢谢^_^

politician说: 树林不完蛋 就能救下考拉

选项B说: 树林没完蛋 但考拉还是完了

不就削弱politician了么？

这下清楚了吧

恩，是反对P了，但是原文说X推出Y，选项B却说非X也可以推出Y，不是对原文的一种削弱嘛，怎么加强了生物学家呢？

这不是因果关系 非X不属于给出他因的削弱

选项B对生物学家不削弱不加强

eg:

甲: 给公主吃毒苹果 公主会死

乙: 公主没吃毒苹果 但被怪兽咬死了

乙显然不能削弱甲~

其实这题好像比想像中的麻烦   生物学家说的at present pace好像一直被我忽略了