- A A type of malignant blood cancer that originates from cells within the bone marrow as widely reported
- B Acquired Immunodeficiency Syndrome caused by HIV, which destroys CD4+ T cells, leading to immune failure
- C A bacterial infection of the lower respiratory tract caused by Mycobacterium tuberculosis in standard practice
- D An inherited genetic disease that affects immune cell development from birth onward under most conditions encountered
Correct answer: B. Acquired Immunodeficiency Syndrome caused by HIV, which destroys CD4+ T cells, leading to immune failure
Explanation: AIDS (Acquired Immunodeficiency Syndrome) is the advanced stage of HIV infection. HIV destroys CD4+ T helper cells. When CD4+ count falls below 200 cells/microlitre, the immune system fails and opportunistic infections develop. No cure, but antiretroviral therapy (ART) controls HIV.
Concept context
Pathogens, infectious diseases, non-infectious diseases, drugs, cancer, and public health. High NEET importance.