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: Ophthalmology
In optic atrophy, the optic disc appears to pale is index of: 
Select and explain. 
A. Atrophy of the nerve fibre, B. Loss of vasculature, C. Gliosis, D. All of the above
B: Loss of vasculature
Answer: B: Loss of vasculature 
Explanation: Ans. Loss of vasculature