56.  Social scientists are underrepresented on the advisory councils of the National Institutes of Health(NIH).  Since these councils advise NIH directors and recommend policy, the underrepresentation of social scientists results in a relative lack of NIH financial support for research in the social sciences.

 If the statements above are correct, they most strongly support which of the following?

(A) A significant increase in the size of NIH advisory councils would be required in order to increase the representation of social scientists on these councils.

(B)A significant increase in the representation of social scientists on NIH advisory councils would result in an increase in NIH funding for social science research.

(C)A significant increase in funding for social science research would result in improved policy recommendations to NIH directors.

(D)A significant increase in funding for the training of social scientists would result in an increase in the number of social scientist on NIH advisory councils.

(E)A significant increase in the representation of social scientists on NIH advisory councils would have to precede any increase in the number of NIH directors who are social scientists.B

请问，如果D中的training 改为正确的research的话，可以吗？

我一直在考虑，A->B,什么时候可以推出 否B-〉否A，什么时候否A-〉否B，有的题就用前者，有的题就用后者，

望讨论

文章说：

非A--》非B

结论是

A--》B

D是：B--》A   错

 我问的就是这个问题

您说的D：B->A    其实不就是结论 非A-〉非B的逆命题吗？

哪里有问题呢？

我问的就是这个问题

您说的D：B->A    其实不就是结论 非A-〉非B的逆命题吗？

哪里有问题呢？

B->A的逆命题 是 A->B

我觉得即使是改了training选项D依然是不对的，因为你没法确认原命题中的推理

A->B是否是充要的，也就是B->A是否正确。

也就是版版说的非A->非B 推出A->B, B->A错