Question

which of the following is an example of reproductive isolation? two populations of finches that cannot produce viable offspring two populations of finches that have different feather colors two populations of salamanders that live in different lakes two populations of salamanders that have different tail lengths

Explanation:

Reproductive isolation refers to barriers that prevent two populations from interbreeding and producing viable, fertile offspring. Among the options, only the inability to produce viable offspring directly relates to this definition. Different physical traits (feather color, tail length) or geographic separation (different lakes) are not reproductive isolation themselves—geographic separation is a prezygotic barrier, but the question asks for an example of reproductive isolation, which the viable offspring criterion directly exemplifies.

Answer:

two populations of finches that cannot produce viable offspring