费费逻辑24 求帮助啊！！！谢谢咯~

Stefaniezhu

24. The interstitial nucleus, a subregion of the brain’s hypothalamus, is typically smaller for male cats than for female cats. A neurobiologist performed autopsies on male cats who died from disease X, a disease affecting no more than .05 percent of male cats, and found that these male cats had interstitial nuclei that were as large as those generally found in female cats. Thus, the size of the interstitial nucleus determines whether or not male cats can contract disease X.
Which one of the following statements, if true, most seriously weakens the argument?
(A) No female cats have been known to contract disease X, which is a subtype of disease Y.
(B) Many male cats who contract disease X also contract disease Z, the cause of which is unknown.
(C) the interstitial nuclei of female cats who contact disease X are larger than those of female cats who do not contract disease X.
(D) Of 1,000 autopsies on male cats who did not contract disease X, 5 revealed interstitial nuclei larger than those of the average male cat.
(E) The hypothalamus is known not to be causally linked to disease Y, and disease X is a subtype of disease Y.

答案是E，解释说：Disease X is the subtype is disease Y, if disease Y has no link with hypothalamus, X must have no link with hypothalamus. 我觉得E成立的话必定需要另外一个假设——即一种病的subtype与该病在感染区域上是一致的，如果只说X是Y的subtype，不能得到结论说X must have no link with hypothalamus呀~  哀，不知道自己是不是钻牛角尖了...

另外，我选的B，说X, Z两种病同时发现，那就有可能是Z引起了X, 而不是the size of the interstitial nucleus，进而削弱argument

不知道自己哪里想错了，求指点！！！非常感谢！！！

babybearmm

C應該改為carefully coordinated with her narratives（illustrations不能發出coordinate的動作）

babybearmm

them多餘

sevenmileser

这个， E里说 The hypothalamus is known not to be causally linked to disease Y，就是那个高亮的 disease Y has no link with hypothalamus,被动句的主动写法；而disease X is a subtype of disease Y，做为作为Y的分支的X, 如果Y没有link，那么X也没有link（类似于，筐里的苹果Y没长虫，所以筐里的红苹果X也没长虫）

Stefaniezhu

谢谢咯，亲~~
先跟你说一声抱歉，我刚又看了我最开始发的内容，发现自己把我的纠结之处写错了....  现在改正了，高亮部分

另外，可以说明一下为什么B错了吗？ 刚又看了一遍发现还是没能分析出B的错因，谢谢咯！！！

sevenmileser

这是个 logic ladder 的问题， all》many》some, 如果我说（前提）班里的同学都是好学生，那么（结论）班里的大多数同学都是好学生， 接下来， 班里有同学是好学生。都是成立。（powerscore 上有的）

B的问题 我相信你在做weaken提的时候应该遇到过， 因果颠倒 这类的问题吧（OG上就有 不和...和睡眠习惯），B犯得就是这类错误，有可能是是Z引起了X，也有可能是X引起了Z，所以不能达到削弱的目的

Stefaniezhu

这是个 logic ladder 的问题， all》many》some, 如果我说（前提）班里的同学都是好学生，那么（结论）班里 ...
sevenmileser 发表于 2012-6-22 07:44

亲，灰常感谢~~~
我再确认一下，看我是否有理解错，B错的原因是因为B在削弱的同时有可能会加强或者无关，所以B不能作为最佳选项？
另外，E的话，Y与该病无关，则X（subtype of Y）也与该病无关？

但是我还是有点纠结之前的误区，Y和Y的亚种X在与该病是否无关上就一定是相互联系的吗？这个和好学生的例子感觉还是有点差异呢？

sevenmileser

你对BE和理解没有问题了 ，如果好学生的例子没能说明白的话，还说筐里的苹果吧， 筐里都是长了虫（有该病）的苹果（如Y），那么筐里的红富士（如X）也是长了虫.的。

Stefaniezhu

哦，恍然大悟！！！
原来是这样理解的，太感谢了，亲~~~