A biologist measures the allele frequencies of pea plants in a very controlled environment. The plants can either have a dominant tall allele (T) or a recessive short allele (t). Which of the following is a reason that this population is not at Hardy-Weinberg equilibrium?

AThe pea plants are mated at random.

BBoth alleles ensure equal survival.

COne pea plant mutates to have a new allele.

DEvery pea plant reproduces exactly once.