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
Which is the most common site for duodenal ulcer 
Select and explain. 
A. Within 2 centimetres of pylorus, B. Second part of duodenum, C. Distal duodenum, D. Early part of jejunum.
A: Within 2 centimetres of pylorus
Answer: A: Within 2 centimetres of pylorus 
Explanation: About 95 percentage of duodenal ulcers occur within 2 centimetres of the pylorus