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': 'Ipratropium bromide is used for \nSelect and explain. \nA. renal colic, B. Organophosphorus poisoning, C. Bronchial asthma, D. miosis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]