When a population is at hardy-weinberg equilibrium which one of the following is true?

a. genotypic frequencies change generation after generation.
b. allele frequencies change generation after generation.
c. the population is a sink for immigrants.
d. one can calculate the recessive allele frequency directly from the homozygous recessive genotype.
individuals of like genotype are most likely to mate.

The correct answer will be option-D

Explanation:

The Hardy-Weinberg principle was given by two different scientists Godfrey Hardy and the Wilhelm Weinberg which worked on understanding the population genetics.

The Hardy- Weinberg equilibrium is based on certain assumptions like population should have no mutations, no emigration, no selective pressure, no migration and the population should be infinite.

Since the Hardy- Weinberg equilibrium is widely used to determine the allelic frequency from the genotype therefore option-D is the correct answer.