This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous System, Subject name: Pathology
[{'content': '5 year old child with posterior fossa mass. Biopsy from the mass shows the following rosettes. \nSelect and explain. \nA. Homer Wright rosette, B. Perivascular pseudorosette, C. Flexner Wintersteiner rosette, D. None', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) Homer Wright rosettes*Type of pseudo rosette in which differentiated tumor cells surround the neuropil seen in neuroblastoma, medulloblastoma, pinealoblastoma', 'role': 'assistant'}]