This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Which of the following tumors is associated with drop metastasis? 
Select and explain. 
A. Astrocytoma, B. Ependymoma, C. Medulloblastoma, D. Oligodendroglioma
C: Medulloblastoma
Answer: C: Medulloblastoma 
Explanation: At the edges of the main tumor mass, medulloblastoma cells have a propensity to form linear chains of cells infiltrating through cerebellar coex to aggregate beneath the pia, penetrate the pia, and seed into the subarachnoid space. Dissemination through the CSF is a common complication, presenting as nodular masses elsewhere in the CNS, including metastases to the cauda equina that are sometimes termed drop metastases. Ref: Robbins 8th edition Chapter 28.