Answer:
D.
Explanation: Ecology: relation of organisms with one another or their surroundings.
Variation allows some individuals within a population to adapt to the changing environment. Because natural selection acts directly only on phenotypes, more genetic variation within a population usually enables more phenotypic variation.
<span>The purpose of the scientific method is to clearly do an experiment by a process of steps helping you keep track, and correct any mistakes.</span>
Im pretty positive the answer to this question is A because RNA contains uracil instead of thymine.
