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
[{'content': 'False about optic atrophy \nSelect and explain. \nA. Disc is chalky white in primary optic atrophy, B. Pallor of disc cannot be correlated with the amount of visual loss, C. Pallor of disc is due to atrophy of nerve fibres, D. All the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Pallor of disc in optic atrophy is due to loss of vascularity.', 'role': 'assistant'}]