This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lens, Subject name: Ophthalmology
[{'content': 'The water content in the lens is \nSelect and explain. \nA. 1%, B. 28%, C. 35%, D. 64%', 'role': 'user'}, {'content': 'Answer: D \nExplanation: (Refer: AK Khurana Comprehensive Ophthalmology, 6th edition, pg no. 181)The lens is composed of 64% water, 35% protein, and 1% lipid, carbohydrate and trace elements. The protein concentration in the lens is actually the highest amongst body tissues. The main types of proteins are alpha (31%), beta (55%) and gamma (2%) crystallins, and insoluble albuminoids (12%)', 'role': 'assistant'}]