Your answer is B, C , and D.
Answer: A
Explanation: It makes the most sense because it isn't directly speaking about something, it is mainly summarizing the main idea. I'm not 100%, but that's the one I would choose if it were me. Hope I helped out a little!
The right answer is B.
Mutations are not always unfavorable, they are often "indifferent" as to the survival of the cells or the individual.
Mutations are the primary source of variation in the genetic material underlying the evolution of living things. They can have a beneficial effect for the species.