Nonrandom mating :
a. affects genotypic frequencies but not allelic frequencies.
b. only occurs when relatives mate.
c. is always harmful when it occurs in populations.
d. can be measured as the probability that two alleles in an individual are identical by state.
e. affects allelic frequencies but not genotypic frequencies.

Answer is A. Affects genotypic frequencies and not allelic frequencies.

Explanation:

Non random mating is when an individual organism prefer to mate with another organism of the same genotype or different genotype.

There are some things that make this to happen. It may be based on physical accessibility or characteristics among others.