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
[{'content': 'Rosenthal fibres are seen in - \nSelect and explain. \nA. Pilocytic astrocytoma, B. Glioblastoma, C. Medulloblastoma, D. Ependymoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Rosenthal fibers are thick, elongated, "corkscrew" eosinophilic bundles that are found on H&E staining of the brain.\nThey are seen\xa0in the presence of long-standing gliosis, pilocytic astrocytoma, Alexander\'s disease (a rare leukodystrophy) and fucosidosis.', 'role': 'assistant'}]