This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunity, Subject name: Pathology
[{'content': 'HIV was discovered in which year? \nSelect and explain. \nA. 1983, B. 1979, C. 1969, D. 1990', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) 1983(Ref: Robbins 9th/pg 243; 8th/pg 236)History of HIV:YearHIV linked developments1981AIDS was first recognized in the United States by U.S. Centers for Disease Control and Prevention (CDC).1983HIV isolated from a patient with lymphadenopathy (HIV 1st discovered)1984HIV demonstrated as causative agent of AIDS1985Enzyme-linked immunosorbent assay (ELISA) was developed to diagnose HIV', 'role': 'assistant'}]