Question

Due to a genetic mutation, a mouse is born with fur that is not as light as fur in other mice of the same population. This makes it easier for the mouse to blend into the environment.

How will this mutation most likely affect the mouse and the population?

The mouse with the mutation will not survive, and the trait will disappear from the population.
The mouse with the mutation will survive and reproduce, and the trait will spread over future generations.
The mouse with the mutation will not survive, but the trait will appear again in the next generation.
The mouse with the mutation will survive and reproduce, but the trait will disappear because it was caused by a mutation.

Answer 1

The mouse with the mutation will survive and reproduce, and the trait will spread over future generations.

Because the darker fur improves camouflage, that mouse has higher survival and reproductive success (higher fitness). Its alleles will therefore increase in frequency in the population by natural selection.