Answer: Natural selection can act on traits determined by alternative alleles of a single gene ... hope this helps, this is one of many answers for this question!
Answer:
I had a long answer that I would have loved to share but I can't because brainly does not like the words using and there is no way around it, tried using every synonym on the internet... LOL sorry
Answer:I think it is part B
Explanation:
The CNS involves the brain and spinal cord and the PNS involves the body nerves.
