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
[{'content': 'The commonest pancreatic tumour is - \nSelect and explain. \nA. Ductal adenocarcinoma, B. Cystadenoma, C. In sulinoma, D. Non islet cell tumour', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. is \'a\' i.e., Ductal adenocarcinoma Grainger writes - "Tumors both benign and malignant, may arise in the exocrine or endocrine tissue of the pancreas. The commonest of these is ductal adenocarcinoma."', 'role': 'assistant'}]