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: Radiology
[{'content': 'Which of the following is a cause of unilateral hyperlucent lung on chest radiography? \nSelect and explain. \nA. Poland syndrome, B. Asthma, C. Acute bronchiolitis, D. Pleural effusion', 'role': 'user'}, {'content': "Answer: A \nExplanation: Poland's syndrome (unilateral congenital absence of pectoral muscles) causes unilateral hypertranslucency.\nAsthma & acute bronchiolitis cause bilateral hypertranslucency.", 'role': 'assistant'}]