This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: CNS Tumors, Subject name: Pathology
[{'content': 'Most common site for medulloblastoma is: \nSelect and explain. \nA. Medulla, B. Cerebellum, C. Cerebrum, D. Pineal gland', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Medulloblastoma usually arise in the midline of the cerebellum (the vermis) in children. In adults, where the incidence is much less than in children, they are more apt to arise in the cerebellar hemispheres in a lateral position. Mostly supratentorial CNS tumors occurs in adults. Infra tentorial tumors occur in childhood.', 'role': 'assistant'}]