The correct answer is option D, that is, genetic diversity among the species.
The sum of genetic characteristics in the genetic makeup of a species is known as genetic diversity. It is differentiated from genetic variability that illustrates the capability of genetic features to change.
The genetic diversity functions as a medium for the populations to amend with the fluctuating environments. With more changes, there is more possibility that some individuals in a population will exhibit different forms of alleles, which are appropriate for the surrounding.
These individuals hold high possibilities of survival in order to generate offspring exhibiting that allele. The population will continue for more generations due to the accomplishment of these individuals.