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: Surgery
[{'content': 'In Couinaud classification, segment IV of liver is: \nSelect and explain. \nA. Caudate lobe, B. Quadrate lobe, C. Right lobe, D. Left lobe', 'role': 'user'}, {'content': "Answer: B \nExplanation: The Couinaud classification divides the liver into 8 independent segments each of which has its own vascular inflow, outflow, and biliary drainage. Because of this division into self-contained units, each can be resected without damaging those remaining.\nIn Couinaud's classification\nSegment I is............. Caudate lobe\nSegment IV is............ Qudrate lobe\nThe caudate lobe is anatomically different from other lobes in that it often has direct connections to the IVC through hepatic veins, that are separate from the main hepatic veins.\nThe caudate lobe may be supplied by both right and left branches of the portal vein.", 'role': 'assistant'}]