Answer:
A. Some pea plants grow slowly and have few offspring
Explanation:
This contrast the reason why Mendel chose pea plants.
They grow rapidly and produce a lot of offspring.
I think it is change to the phenotype of the organism
C.Adenine and guanine<span> are </span><span>purines in DNA.</span>
Do you mean "why"?
They are the main source for all living organisms because they provide energy, relatively short term, for any creature that consumes them.