This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head and neck, Subject name: Surgery
Which is the most common childhood CNS tumor metastasize outside brain 
Select and explain. 
A. Ependymoma, B. Glioblastoma multiforme, C. Choroid plexus tumor, D. Medulloblastoma
D: Medulloblastoma
Answer: D: Medulloblastoma 
Explanation: Medulloblastoma is the childhood brain tumor that most commonly metastasizes extraneuronally."- Nelson Also know There are age-related differences in primary location of tumor. Most common brain tumor in children <1 yr of age -- Choroid plexus tumors (Choroid plexus papilloma and choroid plexus carcinoma ) MC primary brain tumor in adults -- Glioblastoma Multiforme Most malignant primary brain tumor in adults- Glioblastoma Multiforme Ref : Nelson 18/e p2136