This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
[{'content': 'Case finding in RNTCP is based on? \nSelect and explain. \nA. Sputum culture, B. Sputum microscopy, C. X-ray chest, D. PCR antibody detection', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e. Sputum microscopy Sputum smear examination by direct microscopy is the method of choice for case detection. Two sputum samples are collected.", 'role': 'assistant'}]