LSAT TEST20 SECTIONII 的一道题，无从下手，求有经验的开导一下

20.   Ann will either take a leave of absence from Technocomp and return in a year or else she will quit her job there; but she would not do either one unless she were offered a one-year teaching fellowship at a prestigious university. Technocomp will allow her to take a leave of absence if it does not find out that she has been offered the fellowship, but not otherwise. Therefore, Ann will quit her job at Technocomp only if Technocomp finds out she has been offered the fellowship.

Which one of the following, if assumed, allows the conclusion above to be properly drawn?

(A) Technocomp will find out about Ann being offered the fellowship only if someone informs on her.

(B) The reason Ann wants the fellowship is so she can quit her job at Technocomp.

(C) Technocomp does not allow any of its employees to take a leave of absence in order to work for one of its competitors.

(D) Ann will take a leave of absence if Technocomp allows her to take a leave of absence.（D）

(E) Ann would be offered the fellowship only if she quit her job at Technocomp.

看完题后如坠云里雾里，不知所云， 有什么有效的办法解这类题吗？