Answer:
Exhibits genetic variation of the trait present in the population.
Step-by-step explanation:
A genetic trait can have genetic variations in terms of different alleles. A gene can have two or more than two alleles. Since human being are diploid organisms, one individual can carry only two allele for a gene. To study all the possible alleles for a gene that regulate a genetic trait, it is mandatory to have a large same size to make sure all the possible alleles are included.