Retroviruses have an RNA genome. HTLV-1 is a lysogenic retrovirus that establishes a latent infection in human cells. By which of the following mechanisms does infection by a retrovirus such as HTLV-1 most likely cause long-lasting genetic changes to host cells?
a. the host-cell ribosomes translate the viral RNA genome that enters the cell upon initial viral infection
b. the viral RNA polymerase that transcribes host genes has a high error rate
c. the RNA viral genome is reverse transcribed into DNA that integrates into the host genome
d. the RNA viral genome integrates into the host genome