This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lenses, Subject name: Ophthalmology
[{'content': 'Foldable IOL is made of: \nSelect and explain. \nA. PMMA, B. HEMA, C. Polypropylene, D. Acrylic', 'role': 'user'}, {'content': 'Answer: D \nExplanation: INTRAOCULAR LENS-Earliest IOLs were rigid, and made of polymethylmethacrylate (PMMA) or plypropylene. -With the introduction of phacoemulsification and possibility to remove cataract through smaller incisions, foldable materials were developed for IOLs. Foldable IOLs are commonly made of hydrophobic acrylic, hydrophilic acrylic (or hydrogel), and hydrophobic silicone.', 'role': 'assistant'}]