Answer: C
Explanation:
When breeders notice a unique trait of interest and selectively breed to increase their population, there is tendency of also increasing the population of lethal genes. This happens via a situation known as inbreeding depression. There is a tendency to mate closely related individuals in a bid to increase the occurrence of a desired phenotype. However, in a situation where these animals have a recessive lethal gene, it may result in a double recessive thus becoming obvious in the population.