This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pneumonia, Bronchiectasis, and Lung Abscess, Subject name: Medicine
[{'content': 'Most common cause of empyema is: \nSelect and explain. \nA. Bronchopleural fistula, B. Tubercular pneumonia, C. Bacterial pneumonia, D. Pleurisy', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' Bacterial pneumonia .Causes of empyema in decreasing order of frequency.Bacterial pneumoniaT.B. pneumoniaBronchiectasisLung abscess", 'role': 'assistant'}]