Answer:
I'm pretty sure the answer is B
By intruding mutations, which are the ultimate source of biological diversity. I think this is it.
Answer: option D.
Phenotype
Explanation:
Theory of natural selection shows that different organism survive, adapt and reproduce in their environment due to their different phenotypic variation. The phenotypic variation exist among individual organisms and it is heritable which is transfer from one generation to another.
Phenotype are traits or physical characteristics or observable characteristics of organism e.g organisms appearance, behavior e.t.c.
