This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous system, Subject name: Pathology
[{'content': 'Medulloblastoma most commonly metastasize to \nSelect and explain. \nA. Lung, B. CSF, C. Liver, D. Bone', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Spread through the CSF is common, may present as nodular masses anywhere in the CNS. Metastases to the cauda equina are sometimes termed drop metastases. Refer robbins 9/e 844', 'role': 'assistant'}]