The correct answer is c) gene pool.
A gene pool refers to the total collection of genes and their alleles in a given population. It includes all the genetic variations present, making it a crucial concept in understanding the genetic diversity of that population. This genetic diversity is essential for evolutionary processes, as it provides the raw material for natural selection to act upon.
In contrast, a genotype refers to the genetic constitution of an individual, while heterozygosity relates to the presence of different alleles at a gene locus within an individual’s genome. Gene flow, meanwhile, describes the transfer of genetic material between populations, which can alter the gene pool over time. Therefore, when considering all alleles across a population, ‘gene pool’ is the most appropriate term.