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: Surgery
Duhamel operation is done in - 
Select and explain. 
A. Congenital pyloric stenosis, B. Hiatus hernia, C. Achlasia cardia, D. Hirschsprung's disease
D: Hirschsprung's disease
Answer: D: Hirschsprung's disease 
Explanation: Ans. is 'd' i.e., Hirschsprung's disease