Which one of the following produces $AIDS$?

What is the correct sequence of events that occur after $HIV$ infection in a human body?
$(I)$ Viral $DNA$ enters the host $DNA$
$(II)$ Entry into $T_H$ lymphocytes and replication
$(III)$ Viral $RNA$ is converted into viral $DNA$ by reverse transcriptase
$(IV)$ $HIV$ enters into macrophages
$(V)$ Destruction of $T_H$ lymphocytes
$(VI)$ New virus particles are produced from the host cell

$AIDS$ is a disease caused by:

$HIV$ attacks which of the following cells?

The $ELISA$ test is used for the diagnosis of

World $AIDS$ Day is observed every year on: