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': 'Accommodation is due to \nSelect and explain. \nA. Relaxation of ciliary muscles, B. Contraction of ciliary muscles, C. Contraction of dilator pupillae, D. None', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. Contraction of ciliary muscles', 'role': 'assistant'}]