This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Liver, Subject name: Surgery
[{'content': 'Which of the following liver tumor has a propensity to invade the portal or hepatic vein? \nSelect and explain. \nA. Cavernous hemangioma, B. Hepatocellular carcinoma, C. Focal nodular hyperplasia, D. Hepatic adenoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) Hepatocellular carcinomaRef: Sabiston 19/e p 1456* There are two tumors which can grow into veins# HCC# Renal Cell cancer', 'role': 'assistant'}]