Answer:
Genetic drift is simply a change in the frequency of alleles in a population.
Like shown in the comic A, there are different genes present on chromosomes. All of these genes are made up of a pair of alleles. These alleles determine the genotype and the resulting phenotype of an organism.
If none of the alleles is favored by the environment, then a population will have equal no.of all the variant forms of a trait. Like shown in the comic B, both the green and the grey animals are favored equally.
But if natural selection occurs and one form of the allele variant is favored, then a genetic drift will occur. Most of the organisms will have the alleles which are favored by the environment. Like shown in Comic C, where the grey alleles are favored more than the green alleles.
