HIV is best described as

• A. A virus that attacks and destroys the human immune system
• B. A bacteria causing skin infections
• C. A fungus affecting the lungs
• D. A parasite that infects the blood

Answer: (A)

HIV is a virus that attacks and progressively weakens the immune system by infecting CD4 T cells. It’s a virus, not a bacterium, fungus, or parasite, so descriptions of those other organisms don’t fit. Because HIV targets the immune system, the body's defenses become less able to fight infections and illnesses, which is why HIV infection can lead to serious immunodeficiency if not treated. Antiretroviral therapy helps control the virus and preserve immune function.