<u><em>The correct option is C) genetic variation</em></u>
Explanation:
Genetic variation can be described as the differences present in the genetic material i.e DNA of organisms present in a population. Genetic diversity allows organisms of a species to better adapt to an environment. A population in which the genetic variability is scarce might become wiped out by a disease or an invading predator.
As the birds show different variations hence the term that best described them is genetic variation.
The reason for this this that there is a <u>variation</u> (of color) among the colors of the 4 birds. It is helpful to know that feather color is a genetic trait among animals with feathers.
