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