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: Pathology
[{'content': 'A 65 years old smoker presents with chronic cough, hemoptysis and loss of weight. X ray chest shows cavitatory lesion. The most appropriate diagnosis is \nSelect and explain. \nA. Undifferentiated large cell carcinoma, B. Small cell carcinoma, C. Adeno carcinoma, D. Squamous cell carcinoma', 'role': 'user'}, {'content': 'Answer: D \nExplanation: . Squamous cell carcinoma', 'role': 'assistant'}]