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: Surgery
[{'content': 'Commonest symptom of carcinoma bronchus is ? \nSelect and explain. \nA. Hemoptysis, B. Dyspnoea, C. Cough, D. Wheezing', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Cough", 'role': 'assistant'}]