Answer:
Base pairs are found in double-stranded DNA and RNA, where the bonds between them connect the two strands, making the double-stranded structures possible. Base pairs themselves are formed from bases, which are complementary nitrogen-rich organic compounds known as purines or pyrimidines.
Base pair | molecular biology | Britannicahttps://www.britannica.com › ... › Anatomy & Physiology
Explanation:
The answer is A.) artificial selection
I believe (not sure) that the answer is B, viruses must invade their host before being able to reproduce.
I remember seeing a diagram of the general life of a virus, and I remember seeing the virus sticking to a cell, merging in, and reproducing thereafter (sort of like a factory). Once again, I am not sure and the answer may as well be another one.
try posting the question again because you forgot to include the options.