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': 'The lens capsule is produced from the following structure: \nSelect and explain. \nA. Lens epithelium, B. Lens fibers, C. Ciliary body, D. Vitreous humor', 'role': 'user'}, {'content': "Answer: A \nExplanation: The lens is composed entirely of epithelium surrounded by a capsule. The lens epithelium secretes the lens capsule and regulates the transpo of metabolites, nutrients and electrolytes to the lens fibers. The lens epithelium is a single layer of cells lining the capsule. The cells are of two types: those in the central zone that are not actively dividing, and cells in the pre-equatorial germinative zone that give rise to the lens fibers. Ref: Parsons' Diseases of the Eye By Ramanjit Sihota & Radhika Tandon, 2011, Page 257.", 'role': 'assistant'}]