This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Health programmes in India, Subject name: Social & Preventive Medicine
[{'content': 'Number of center of excellence in vision 2020- \nSelect and explain. \nA. 20, B. 200, C. 2000, D. 20000', 'role': 'user'}, {'content': 'Answer: A \nExplanation: 20 Centre of excellence in vision 2020 Functions are Professional leadership Strategy development CME Laying of standards and quality assurance Research Ref: PARK&;S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICINE 23rd edition pg 440', 'role': 'assistant'}]