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': 'Maxwell Lyon sign is seen in: \nSelect and explain. \nA. Spring catarrh, B. Dendritic ulcerative keratitis, C. Symphathetic ophthalmitis, D. Angular conjunctivitis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Spring catarrh', 'role': 'assistant'}]