A Population May Eventually Stop Responding to Artificial Selection Because

A population may eventually stop responding to artificial selection because:

A) individuals in the population have become homozygous for the alleles responsible for the trait.
B) natural selection opposes any further change in the characteristic.
C) natural selection can no longer enhance the results of artificial selection.
D) individuals in the population have become homozygous for the alleles responsible for the trait and natural selection opposes any further change in the characteristic.
E) individuals in the population have become homozygous for the alleles responsible for the trait and natural selection can no longer enhance the results of artificial selection.