Which of the following statements is true?

a) viruses are bigger than bacteria.
b) viruses conduct cellular respiration like any other living organism.
c) viruses have both rna and dna.
d) viruses cannot be cultured on artificial laboratory media of any kind.

the answer to your question is:

c. complementary base-pairing

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.

the correct answer is:

a population changes in response to a change in the environment.