This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Human Immunodeficiency Virus, Subject name: Microbiology
[{'content': 'Most common agent causing tuberculosis in AIDS patient in tropical countries is: \nSelect and explain. \nA. Mycobacterium tuberculosis, B. Mycobacterium intracellulare1997, C. Mycobacterium parvum, D. Mycobacterium atypical', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Mycobacterium tuberculosis (Ref: Ananthanarayan, 9th/e, p. 576 and 8th/e, p. 575)Common pathogens causing T.B. in AIDS patients are M. tuberculosis and M. avium intraceliulare. In developing countries, the most important pathogen is M. tuberculosis, with many strain being multidrug resistant.", 'role': 'assistant'}]