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': 'A child with acute respiratory distress shows hyperinflation of unilateral lung in chest X-ray. Most likely cause for above presentation is: \nSelect and explain. \nA. Staphylococcal bronchopneumonia, B. Aspiration pneumonia, C. Congenital lobar emphysema, D. Foreign body aspiration', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Foreign body aspiration is the commonest cause of acute lung collapse in a child. Ref: Chest Radiology: The Essentials By Jannette Collins, Eric J. Stern, 2007, Page 196', 'role': 'assistant'}]