[讨论]陈向东的一道逻辑题目

Question : Most parents who are generous are good parents , but some self-centered parents are also good parents ..Yet all good parents share one characteristic: they are good listeners.

If all of the statements in the passage are true, which on eof the following must also be true?

(a) All parents who are good listeners are good parents .

(b) some parents who are good listeners are not good parents.

(c) Most parents who are good listeners are generous .

(d)Some parents who are good listeners are self-centered.

(e)fewer self-centered parents than generous parents are good listeners.

此题目的正确答案是D，我也赞同，但是我认识B 选项也是对的。为什么不选？

let us assume: good parents =A        good listeners=B

the passage tell us A->B

the answer B says:  B->notA

obviously, the passage not tell us this infornation