PT 21 S2 Q20

Ann will either take a leave of absence from Technocomp and return in a ... ...

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) ...
(C) ...
(D) ...
(E) ...

*This question is included in Necessary Premise: Intro Set