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
A child with acute respiratory distress shows hyperinflation of unilateral lung in chest X-ray. Most likely cause for above presentation is: 
Select and explain. 
A. Staphylococcal bronchopneumonia, B. Aspiration pneumonia, C. Congenital lobar emphysema, D. Foreign body aspiration
D: Foreign body aspiration
Answer: D: Foreign body aspiration 
Explanation: 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