This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Neuro-ophthalmology, Subject name: Ophthalmology
[{'content': 'Optic nerve is - \nSelect and explain. \nA. Second order neuron, B. First order neuron, C. Fouh order neuron, D. Third order neuron', 'role': 'user'}, {'content': 'Answer: A \nExplanation: each optic nerve stas from optic disc and extends up to optic chiasma where the two nerves meet. It is the backward continuation of the nerve fibre layer of retina , which consists of the axons originating from the ganglion cells ie second order neuron. Reference: textbook of comprehensive Opthalmology by AK Khurana.', 'role': 'assistant'}]