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: Pediatrics
True about Hirshprug's disease – 
Select and explain. 
A. Aganglionic segment is contracted not dilated, B. Descending colon is most common site, C. Barium enema is diagnostic, D. Barium enema shows calcification
A: Aganglionic segment is contracted not dilated
Answer: A: Aganglionic segment is contracted not dilated 
Explanation: None