Data Sufficiency

Taking Stmt (1) alone,
r < 4 can have Prime numbers infinite, ( considering -ve int also )
Taking Stmt(2) alone, No Clue for "r"

Taking Both (1) and (2),
q=18, and r < 4, q = 2x3x3. clue is it asks if "q is a multiple of r" and Not the value of "r".

Hence Both Stmt are sufficient to ans.

Had the question being "If q is a multiple of prime numbers, what is value of r? "...my ans would be NONE OF THE STMTS.

what's the OA

In my opinion, the answer is E.

The question does not say that r is an integer. So r could be 3/7 or r could be -500.

So both (1) and (2) are insufficient.