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': 'Macular edema is caused by all except: \nSelect and explain. \nA. Microaneurysm, B. Cap dilatation, C. Neovascularization, D. None', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. None', 'role': 'assistant'}]