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
True about left renal vein is? 
Select and explain. 
A. Posterior and inferior to sup. mesenteric aery, B. Posterior and superior to superior mesenteric aery, C. Anterior and inferior to sup. mesenteric aery, D. Annterior and superior to sup. mesenteric aery.
A: Posterior and inferior to sup. mesenteric aery
Answer: A: Posterior and inferior to sup. mesenteric aery 
Explanation: Posterior and inferior to sup. mesenteric aery. The left renal vein along with third pa of duodenum lies in the aoo-mesenteric angle space. The left renal vein lies in front of left renal aery and posterior to the pancreas, splenic vein and sup. mesenteric aery. The superior mesenteric aery extends anteriorly and inferiorly off the aoa at L1 veebral level.