Explain how a mutation might lead to adaption.

An adaptation is a mutation, or genetic change, that helps an organism, such as a plant or animal, survive in its environment. Due to the helpful nature of the mutation, it is passed down from one generation to the next. As more and more organisms inherit the mutation, the mutation becomes a typical part of the species. The mutation has become an adaptation.

one comes through sex and the other does not lul im not

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."