This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Surgery
[{'content': 'In Budd Chiari syndrome, the occlusion is at the \nSelect and explain. \nA. IVC, B. Renal Vein, C. Hepatic vein, D. Splenic vein', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Budd chiari syndrome occurs when venous drainage of the liver is occluded by hepatic venous thrombosis or obstruction from a venous web Reference Bailey and love&;s 24 the edition page no.1074', 'role': 'assistant'}]