The answer is letter C. | <span> Slight differences in the color of feathers in
birds are the result of mutations. Mutation is process that occurs through a
long period of time. It is a process in which the genes’ structures changes
thus altering the physical characteristics and behaviors of species. This
results into variant forms that may be transmitted to the next generations of
species. Mutation is caused by an alteration of single base units in DNA, or
the deletion, insertion, or rearrangement of larger sections of the genes or
chromosomes. </span>
