16. If n and k are integers whose product is 400, which of the following statements must be true?
(A) n + k > 0
(B) n ≠ k
(C) Either n or k is a multiple of 10.
(D) If n is even, then k is odd.
(E) If n is odd , then k is even

OA is E. Aren't E & D the same? I got C instead. Kinda confused.