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': 'Maximum refractive index ? \nSelect and explain. \nA. Cornea, B. Air, C. Lens, D. Vitreous', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Lens Lens has maximum refractive index among the refractive structures of eye. The refractive indices of the successive layers of lens increase from the periphery towards the nucleus.", 'role': 'assistant'}]