This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Childhood Tumors, Subject name: Pediatrics
[{'content': 'Which of the following childhood tumors show extracranial metastasis? \nSelect and explain. \nA. Glioblastoma multiforme, B. Medulloblastoma, C. Choroid plexus carcinoma, D. Ependymoblastoma', 'role': 'user'}, {'content': "Answer: B \nExplanation: b. Medulloblastoma(Ref: Nelson's 20/e p 2453-2460, Ghai 8/e 612-613)Among the given options, Medulloblastoma is the most malignant brain tumor seen in children. Up to 30% of patients with medulloblastoma present with neuroimaging evidence of leptomeningeal spread.", 'role': 'assistant'}]