Answer: The correct answer is:
The another genetic variation among humans that might be an adaptation to the environment is colour of the skin. That is, people live in warmer place have dark colour of skin. This dark colour protects them from Ultraviolet (UV) radiation.
What is adaptation?
Any heritable trait that helps an organism to survive and reproduce in its environment.
Organisms such as plants, animals, human beings and all living things.
For example, a plant growing at an increasing altitude could alter its metabolism.
Explanation: I use britain-english so don't mind colour