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: Anatomy
[{'content': "Brunner's glands are seen in - \nSelect and explain. \nA. Jejunum, B. Upper duodenum, C. Lower duodenum, D. Appendix", 'role': 'user'}, {'content': 'Answer: B \nExplanation: The presence of mucous duodenal (Brunner’s) glands in the submucosa is indicative of upper duodenum. These submucosal glands are absent in the jejunum, ileum and the entire large intestine.', 'role': 'assistant'}]