Answer: D
Explanation: Hardy-Weinberg (H-W) principle assumes the following;
1. Random mating
2. No migration
3. No selection
4. No mutation
5. Large population
When genotype frequencies in a population deviate from H-W principle, it takes only one (1) generation of random mating to H-W equilibrium if the above assumptions hold, that the frequencies in males and females are equal and that the locus is autosomal.
In the case of different allele frequencies between the sexes, it will take two (2) generations of random mating to H-W equilibrium.
Also, it will take multiple generations to attain equilibrium for sex-linked loci because one sex has two copies of the gene and the other sex has only one.