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: Dental
[{'content': 'COPRA came into existence on: \nSelect and explain. \nA. 15th April, 1986, B. 15th April, 1987, C. 15th April, 1988, D. 15th April, 1989', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]