Explain Why HIV Becomes Resistant So Quickly When a Single

Explain why HIV becomes resistant so quickly when a single drug is used therapeutically.

A) The virus is an RNA genome virus. By using host RNA polymerase to directly copy the genome to make more virus particles, there's no proofreading capability. This leads to a high rate of mutation of the viral genome and increased chance for drug resistance.
B) HIV uses reverse transcriptase to make a cDNA version of its RNA genome. This polymerase is "'sloppy," with a high rate of error and lack of a proofreading capability. This leads to a high rate of mutation of the viral genome and increased chance for drug resistance.
C) HIV synthesizes a protein enzyme that directly cleaves anti-HIV drugs, giving it a characteristically high rate of resistance to a single drug type.
D) HIV is constantly changing its genetic structure by swapping genetic elements with other virus strains. This leads to a high rate of mutation of the viral genome and increased chance for drug resistance.
E) Like bacteria, HIV undergoes spontaneous mutation in the presence of antibiotics, so multiple medications are used simultaneously to reduce the chance of this happening.