Answer:
Recent studies have shown that dark skin colour was developed in the past for protection against cancer. Scientists claim that in the past natural selection favoured humans having dark colour as compared to humans having a fair colour. This is because humans having a darker colour produced more melanin which protected them from ultraviolet radiation. As a result, this skin colour protected more against skin cancer. Hence, Having a darker skin colour protected in survival and reproduction to people thousands of years ago.
Geographic Isolation Because i had bio last year an i remember that Exact Question
Answer:
I believe it's B, its been a while since I last studied cells so I might be wrong
Explanation:
Crustaceans, insects, spiders, lobsters, clams, etc.
The word that goes on to the gap is "cells"
Hope it helped!