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': 'A patient with sputum positive pulmonary tuberculosis is on ATT for the last 5 months but the patient is still positive for AFB in the sputum. This case refers to - \nSelect and explain. \nA. New case, B. Failure case, C. Relapse case, D. Drug defaulter', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Failure case", 'role': 'assistant'}]