Dogs and pigs are members of different species because:

A. of prezygotic barriers to their ability to breed.
B. hybrids between them are infertile.
C. one is a predator, and the other is prey.
D. they are at the far end of the ring in a ring species.

C. One is a predator, and the other is prey.

Explanation:

They are not the same animal and they may not like each other, one may be friendly and the next one is not.

well, i believe that the answer is 2. : 3

you know they are heterozygous for a trait because they have it as jj or jj.