This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax And Mediastinum, Subject name: Surgery
[{'content': 'Commonest cause of lung abscess: \nSelect and explain. \nA. Aspiration, B. Hematogenous spread from distant site, C. Direct contact, D. Lymphatic spread', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Lung Abscess Lung abscess refers to a microbial infection of the lung that results in necrosis of the pulmonary parenchyma MC cause of primary lung abscess: Anaerobic bacteria Etiology of anaerobic lung abscess: Aspiration', 'role': 'assistant'}]