The graph illustrates the frequencies of two genotypes, AA and Aa, over many generations. The recessive condition, aa, results in sickle cell anemia. Wince this is a recessive condition, individuals with Aa or AA do not display the sickle cell phenotype. What statement explains what is shown in the graph beyond generation 35 for this gene?
A) Individuals with the heterozygous condition replaced individuals with either homozygous condition.
B) All of the individuals with aa phenotype died, leaving only individuals displaying the dominant phenotype.
C) Females preferred mating with Aa individuals, resulting in a continued presence of the recessive (a) allele.
D) The population reached equilibrium for this trait, as the genotype frequencies stabilized after 35 generations.