Mini humans exposing the skin to sunlight or a prolonged period of time results in the production of more pigment by the skins tanning this change in skin color provides evidence that

This change in skin color provides evidence that the environment can influence gene action.

Explanation:

Many studies have revealed that the physical traits of a person are attributed to the genetic makeup as well as the environmental characteristics. Some traits depend on both the factors. Environmental factors can determine which genes would be turned on or off or it might control the expression rate of a gene.  For example, two identical twins might have different skin colour if one works in sunlight and the other works indoors.

the correct answer is:

a population changes in response to a change in the environment.