What is the CD4 count diagnostic for AIDS?

Rationale: A. AIDS (Acquired Immunodeficiency Syndrome) is diagnosed in an HIV-positive individual when the CD4+ T-lymphocyte count falls below 200 cells/mm³ or when the patient develops opportunistic infections or AIDS-defining illnesses. B. Less than 400 or 400 – This represents a normal or near-normal immune function, not diagnostic for AIDS. D. More than 200 or >200 – A CD4 count above 200 suggests HIV infection without progression to AIDS.