The Following Questions Refer to the Following Paragraph

Multiple Choice

The following questions refer to the following paragraph.
HIV's genome of RNA includes the code for reverse transcriptase (RT) , an enzyme that acts early in infection to synthesize a DNA genome off of an RNA template. The HIV genome also codes for protease (PR) , an enzyme that acts later in infection by cutting long viral polyproteins into smaller, functional proteins. Both RT and PR represent potential targets for antiretroviral drugs. Drugs called nucleoside analogs (NA) act against RT, whereas drugs called protease inhibitors (PI) act against PR.
-HIV has nine genes in its RNA genome. Every HIV particle contains two RNA molecules, and each molecule contains all nine genes. If, for some reason, the two RNA molecules within a single HIV particle do not have identical sequences, then which of these terms can be applied due to the existence of the nonidentical regions?

A) homozygous
B) gene variability
C) nucleotide variability
D) average heterozygosity
E) All but one of the responses are correct.