This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Small and Large intestine, Subject name: Anatomy
[{'content': 'Which of the following is anteriorly related to third pa of duodenum: \nSelect and explain. \nA. Poal vein, B. Head of pancreas, C. Hepatic aery, D. Superior mesenteric vein', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Superior mesenteric vein (and aery) cross the anterior to the third pa of the duodenum to enter the mesentery of small intestine. Head of pancreas is in superior relation. Relations : anteriorly: small bowel mesentery root and sup. mesentric aery. :posteriorly: right psoas muscle, right ureter, gonadal vessels, aoa and IVC.', 'role': 'assistant'}]