Which statement best explains how cellular respiration helps maintain homeostasis in animals

As a small change in a person's dna can cause a genetic disorder

Many farmers prefer cattle without horns because it is safer for their herds. the allele for no horns (n) is dominant to the allele for the presence of horns (n). a farmer mates a male with horns to a heterozygous female without horns. what is the chance that the offspring will have horns?

This is a biological reaction due to a stimulus. i need this quickly !