which of the following is an example of reproductive isolation?○ two populations of finches that cannot…

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
Answer
Brief Explanations:
Reproductive isolation refers to barriers that prevent two groups from producing viable, fertile offspring or from mating successfully. Physical traits like feather color/tail length are not reproductive barriers, and living in different lakes is geographic isolation (a pre-zygotic barrier but not direct reproductive isolation in the sense of failed reproduction). The inability to produce viable offspring is a post-zygotic reproductive isolation barrier.
Answer:
two populations of finches that cannot produce viable offspring