Question

f m and p are positive integers and (m + p) x m is even, which of the following must be true?
A. If m is odd, then p is odd.
B. If m is odd, then p is even.
C. If m is even, then p is even.
D. If m is even, then p is odd.

I choose C is that correct

Answer 1

I choose C but not sure if that's correct

Answer 2

for addition:
the sum of 2 odds is even
e.g. 3+5 = 8
the sum of 2 evens is even
the sum of an even and an odd is odd
e.g. 3 + 4 = 7

for multiplication:
odd x odd = odd, e.g. 3x5=15
even x even = even , e.g. 6x8 = 48
even x odd = even , 4 x 5 = 20

assuming x is also an integer and we have (m+p)(x), it will depend on whether x is even or odd

I suggest you take some actual values of m , p, and x
and test the cases.
The you will be sure of your choice.