Question

Within any large animal population, there is _______ a variety of traits. And between different animal populations, there is _______ a variety of traits.
 A. never; sometimes B. always; always C. never; always D. sometimes; sometimes

Answer 1

The answer to this question is either B or D, though it would probably be B.

Answer 2

Within any large animal population, there is always a variety of traits. And between different animal populations, there is always a variety of traits.

Option B is correct.

These traits are the expression of genes that are copied and passed on to offspring during reproduction.

Moreover, new traits can come from transfer of genes between populations, as in migration, or between species, in horizontal gene transfer.