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: Pharmacology
[{'content': 'Drug causing megaloblastic anemia is : \nSelect and explain. \nA. INH, B. Chloramphenicol, C. Pyrimethamine, D. Methyldopa', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]