What is the full form of the $WB$ test?

Which of the following effects is observed in an individual infected with $HIV$?

Which of the following is a symptom of full-blown $AIDS$?

$HIV$,which causes $AIDS$,first starts destroying:

The immune system of a person is suppressed. In the $\text{ELISA}$ test,he was found positive to a pathogen.
$(a)$ Name the disease the patient is suffering from.
$(b)$ What is the causative organism?
$(c)$ Which cells of the body are affected by the pathogen?

Which diagnostic test is suggested for patients suspected of having $AIDS$?