Originally Posted by
DemonGeminiX
For the problem in it's current form, the correct reply is "none of the answers are correct".
If you wanna change the answers, then if "25%" is listed only once, or (and that's an exclusive or, btw) if "50%" is listed twice, but then you'd have to indicate that both of the two "50%" answers are correct, but then again, that's not really what the problem is asking, now isn't it? It's asking to choose one answer at random. No matter. Out of a choice of four, "60%" could never be correct.
Change one of the "25%" to something else, then the singular remaining "25%" would be correct.