Answer
(e)
Work Step by Step
Retroviruses contain reverse transcriptase to form a complementary strand of DNA, which is then replicated to form double-stranded DNA (dsDNA). dsDNA must migrate to the cell nucleus and integrate into the chromosomes of the host, whereby it becomes a provirus. Retroviruses cause tumors and leukemia in rodents, birds, and humans and also causes acquired immune deficiency syndrome (AIDS) in humans.
