Answer:
a) Skin color in humans is an example of continuous variation.
Step-by-step explanation:
This variation is difference in DNA and it changes in the body among various individuals.
Every person does not have the same skin color, hair, height, and weight. It is different in every individual. The difference in physical traits in which a series of types are characterized on a continuous extent rather than being assembled into distinct categories is known as continuous variation.
When numerous genes perform a combined effort, continuous variation takes place.