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': 'Chalky white optic disc on fundus examination is seen in all except- \nSelect and explain. \nA. Syphilis, B. Lebers hereditary optic neuropathy, C. Post papilledema optic neuritis, D. Traumatic injury to the optic nerve', 'role': 'user'}, {'content': "Answer: C \nExplanation: Chalky white disc is seen in primary optic atrophy. Trauma to optic nerve, Tabes dorsalis (syphilis), and Leber's hereditary neuritis can cause primary optic atrophy.\nIn post papilledematous (Secondary) optic atrophy the disc is pale or dirty/ grey disc.", 'role': 'assistant'}]