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': 'Sudden painful diminition of vision in\nAnterior Uveitis is due to \nSelect and explain. \nA. Blood in Anterior chamber, B. Cells in Anterior chamber, C. Edema of Cornea, D. Ciliary muscle spasm', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Due to ciliary muscle spasm, convexity of lens increases leading to blurred vision and pain due to spasm.', 'role': 'assistant'}]