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': 'Is not true about soft exudates (cotton wool patches on retina): \nSelect and explain. \nA. Are a sign of retinal hypoxia, B. Formed due to swelling of nerve fibre layer, C. Frequently change their shape, D. In late stages are conveed into hard exudates', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. In late stages are conveed into hard exudates', 'role': 'assistant'}]