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: Anatomy
[{'content': 'Type II cholangiocarcinoma involve \nSelect and explain. \nA. Division of both ducts and not extending outside, B. Common hepatic duct only, C. Secondary hepatic duct, D. Extending beyond hilum', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Bismuth - corlette classification of Hilar Cholangiocarcinoma Type I- Tumor confined to hepatic duct, not involving the main biliary confluence Type II- Tumor involving the main biliary confluence but not extending to the right or left ducts Type IIIa- Tumor extending upto the right secondary biliary confluence Type IIIb- Tumor extending upto the left secondary biliary confluence Type IV - Tumor extending bilaterally to the secondary biliary confluence Ref : Sabiston 20th edition Pgno :1514-1518', 'role': 'assistant'}]