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 most earliest sign of anterior uveitis is: \nSelect and explain. \nA. Aqueous flare, B. Keratic precipitates, C. Constriction of pupil, D. Raised intraocular pressure', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. Aqueous flare', 'role': 'assistant'}]