If a and b are unique prime integers, which of the following must be odd?\nOptions:\n(A) a−b\n(B) 2a+2b\n(C) 2a−2b\n(D) 2a / 2b\n(E) ab^2
Stream of thoughts:
(A)
Any number multiplied by 2 has to be an even number.

hence.

The answer is (A)