Respuesta :
The correct answer is: B. They have a higher risk of mating with a related mate
The effect that happened to the deer is called bottleneck effect. Bottleneck occurs when a population's size is reduced due to environmental events such as earthquakes, floods, fires, diseases..The genetic variation in that population is decreased and the same genes are passed in the next generation. As the result, the chances of inbreeding and genetic homogeneity can increase.
Genetic diversity might increase when genes flow from another population.