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
Cause of Opaque hemithorax 
Select and explain. 
A. Poland's syndrome, B. Mcleod's syndrome, C. Congenital lobar emphysema, D. Foreign body
D: Foreign body
Answer: D: Foreign body 
Explanation: A, b, c are causes of U/L hypertranslucent hemithorax.