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': 'Most common type of senile cataract- \nSelect and explain. \nA. Cunieform, B. Nuclear, C. Cupuliform, D. None', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Most common type of senile cataract is cunieform coical (70%) followed by nuclear (25%) and cupuliform.', 'role': 'assistant'}]