The fact that there is considerable variation among individuals in height, eye color, and other characteristics demonstrates mendel's law of

This demonstrates Mendel's law of independent assortment.
The law of independent assortment refers to the independent separation of different genes when the reproductive cells are formed. Mendel's experiments included crosses of organisms that differed in two traits. He observed that the combinations of traits in the offspring did not always match the combinations of traits in the parent organisms.