If the positive integer \(x\) is a multiple of \(4\) and the positive integer \(y\) is a multiple of \(6,\) then \(xy\) must be a multiple of which of the following?

I. 8
II. 12
III. 18

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

Answer: B

Source: Official Guide