This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Abdomen and pelvis, Subject name: Anatomy
[{'content': 'Relation of renal vein with aoa is \nSelect and explain. \nA. Anterior, above SMA, B. Anterior, below SMA, C. Anterior, below IMA, D. Posterior, below SMA', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Because the inferior vena cava is on the right half of the body, the left renal vein is generally the longer of the two.', 'role': 'assistant'}]