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
Best way to diagnose lower small intestinal obstruction 
Select and explain. 
A. Pain abdomen, B. Abdominal distension, C. Profuse vimitting, D. Multiple air gas shadows on X - ray
D: Multiple air gas shadows on X - ray
Answer: D: Multiple air gas shadows on X - ray 
Explanation: None