PS Archive | Re: If 375y = x2 and x and y are positive integers, then which of the foll

If 375y = x2 and x and y are positive integers, then which of the following must be an integer?

(1) y/15
(2) y/30
(3) y^2/25

(A) I only
(B) III only
(C) I and II only
(D) I and III only
(E) I, II, and III only

The question ask for MUST be true option. I think none of the option must be true.
Please any body explain in details.