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': 'A healed patch of chorioretinitis gives rise to: \nSelect and explain. \nA. Negative scotoma, B. Positive scotoma, C. Both of the above, D. None of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. Negative scotoma', 'role': 'assistant'}]