Answer:
From the given Options, Option C is correct.
the inheritance of the alleles from each parent is completely random but in a population, there may be natural selective pressure from the environment to favor different levels of expression
Step-by-step explanation:
The evolutionary basis of human skin color stems far back to the genetic mutations involved in skin pigmentation. Although the diversity of skin color is a characteristic trait of humans, These variants and their evolution reveal that the history of skin color is much older than previously thought.
The evolution of various variations in the human skin color is a result of selective forces which is an environmental factor that favors various levels of expression. Thus, the best option that explains the basis of human skin color in terms of evolutionary trend is Option C.