Final answer:
HIV causes AIDS by infecting and destroying helper T cells in the immune system, leading to severe immunodeficiency. As a result, the body is unable to defend against opportunistic infections and diseases, which are often the immediate cause of death in affected individuals.
Step-by-step explanation:
How does HIV cause AIDS?
The correct answer to the question is c) HIV is a RNA virus which parasitizes the immune system cells. HIV, or human immunodeficiency virus, is a retrovirus that contains RNA. Once inside the body, HIV primarily targets helper T cells, also known as CD4+ T cells, which are a crucial component of the human immune system. HIV infects these cells, uses them to replicate, and then destroys them. Over time, this leads to a dramatic decline in the number of helper T cells in the body, weakening the immune system and allowing opportunistic infections and cancers to thrive, conditions typically resisted by a healthy immune system. This stage, characterized by severe immune system damage, is known as acquired immunodeficiency syndrome, or AIDS.
AIDS is diagnosed when the CD4+ T cell count falls to a critically low level and the individual begins to suffer from these opportunistic infections and cancers. Since the body can no longer defend itself effectively, these secondary infections and diseases often lead to the death of the patient rather than the HIV infection itself.
HIV transmission can occur through contact with infected body fluids such as blood, semen, vaginal fluid, and breast milk. It's important to note that bodily fluids like saliva, sweat, and tears do not transmit HIV.