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
Most common type of optic nerve glioma is- 
Select and explain. 
A. Gemistocytic, B. Fibrous, C. Protoplas, D. Pilocytic
D: Pilocytic
Answer: D: Pilocytic 
Explanation: Slow growing tumour arising from the astrocytes. .occurs in first decade of life. Ref: ak khurana 6th edition