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': 'Posterior relations of head of pancreas are all except - \nSelect and explain. \nA. Common bile duct, B. First part of duodenum, C. Aorta, D. Inferior vena cava', 'role': 'user'}, {'content': 'Answer: B \nExplanation: First part of duodenum is anterior to head of pancreas.\nIVC and common bile duct are posterior to head of pancreas.\nOption C is tricky here. Aorta is posterior to uncinate process which in turn is a part of head of pancreas.', 'role': 'assistant'}]