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: Medicine
[{'content': 'Klebsiella pneumonia is \nSelect and explain. \nA. Lobar pneumonia with absent air bronchogram sign, B. Involves lower lobe predominantly, C. Cavitation is common, D. Pleural effusion is not commonly seen', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Klebsiella pneumonia :\n\nAir\xa0bronchogram sign positive.\nInvolves upper lobe.\nCavitations and pleural effusion is common.', 'role': 'assistant'}]