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
Colon cut off sign in plain X-Ray of abdomen is seen in? 
Select and explain. 
A. Mesenteric ischemia, B. Intussusception, C. Acute pancreatitis, D. Acute cholangitis
C: Acute pancreatitis
Answer: C: Acute pancreatitis 
Explanation: Abrupt termination of the gas within the colon at the level of the radiological splenic flexure is called colon cut off sign. Inflammatory infiltration of the phrenicocolic ligament leads to the spasm of the colon and lumen narrowing at the level where colon returns to retroperitoneum.