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
Most common site of gall stone impactation is - 
Select and explain. 
A. Duedenojejunal junction, B. Proximal to iliocaecal junction, C. Distal to iliocaecal junction, D. Colon
B: Proximal to iliocaecal junction
Answer: B: Proximal to iliocaecal junction 
Explanation: Ans is 'b' i.e., Proximal to Ileocaecal junction