Change in the frequency of alleles at a locus that occurs by chance is called:

Explanation

Genetic drift takes place when the occurrence of variant forms of a gene, called alleles, increases and decreases by chance over time. These variations in the presence of alleles are measured as changes in allele frequencies.Genetic drift is the change in the frequency of gene variants (alleles) in a population due to random chance events, rather than natural selection. It can cause rare alleles to become common or common alleles to be lost entirely, leading to a reduction in genetic variation. The effects of genetic drift are most pronounced in small populations, where random events can have a disproportionately large impact.