Which expression is even for all integers a and b?
a) 2a + b
b) ab + 2a
c) 5a + 6b
d) ab + 2b
e) ab + ab

Considering that the multiplication of a number by 2 always results in an even number, the correct option is:

E) ab + ab

In option E, the equivalent expression is:

A number multiplied by 2 is always even, thus, the expression is even for all integers.

A similar problem is given at link

Pretty sure it's ab + ab

Step-by-step explanation:

Taking the test myself.. if it needs to be even for all integers and it doesn't give us numbers for a or b then ab + ab is the only "even for all integers"