The example of variation is C. Two Guinea pigs having different colored fur.
Variation refers to the differences that exist between individuals of the same species. While identical twins have identical DNA, they can still differ in various ways, such as their height, weight, or personality traits. Two potato plants that are clones of each other are genetically identical and therefore do not exhibit variation. Two human beings having similar body parts is a vague statement and does not clearly indicate variation. However, two Guinea pigs having different colored fur is a clear example of variation, as it highlights differences in physical characteristics between two individuals of the same species.