急！求解逻辑题GMAT Verbal Review 2nd edition Q7

sherrytyu

A researcher discovered that people who have low levels of immune-system activity ten to score much lower on tests of mental health than do people with normal or high immune-system activity.  The researcher concluded from this experiment that the immune system protects against mental illness as well as against physical disease.

The researcher's conclusion depends on which of the following assumptions?


(A) High immune-system activity protests against mental illness better than normal immune-system activity does.
(B) Mental illness is similar to physical disease in its effects on body systems.
(C) People with high immune-system activity cannot develop mental illness.
(D) Mental illness does not cause people's immune-system activity to decrease.
(E) Psychological treatment of mental illness is not as effective as is medical treatment.


本人实在一头雾水，求哪位ＮＮ帮忙解答一下。此题答案为Ｄ,但我个人觉得B对。实在看不懂题意......

sherrytyu

多谢解答！现在才明白考点是什么！继续努力中......争取touch到牛尾巴，哈哈

mengyizheng

我的理解：
          A                               B
 免疫系统不活跃-------脑袋不健康
 正常或活跃--------健康
（这只是两个事实，并没有说明哪个引起哪个，中间没有因果关系。）
结论：免疫系统会避免脑袋有病  A决定B

而B讨论一个整体中的两部分之间的比较是无关比较，对结论没有支持作用

文中假设了不是因为B引起的A，即，原文结论的因果没有倒置，结论成立