Which one of the following produces $AIDS$?

The genome of $HIV$ replicates in the macrophages with the help of an enzyme called:

Which of the following is true regarding $HIV$,the agent responsible for $AIDS$?

$A$ doctor,while operating on an $HIV$ patient,accidentally cut himself with a scalpel. He comes to you,suspecting that he may have contracted the virus. Which test will you advise him to perform to rule out or confirm his suspicion?

The cause of $AIDS$ is ..........

Which of the following is a preventive measure for $AIDS$?