This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tumors, Subject name: Ophthalmology
[{'content': 'Most common type of optic nerve glioma is- \nSelect and explain. \nA. Gemistocytic, B. Fibrous, C. Protoplas, D. Pilocytic', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Slow growing tumour arising from the astrocytes. .occurs in first decade of life. Ref: ak khurana 6th edition', 'role': 'assistant'}]