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': 'A boy 10-year-old, fractured his central incisor 1 ½ year\nback. His pulp test is negative. What is the treatment: \nSelect and explain. \nA. Debridernent of pulp space and apexification, B. RCT, C. Debridement and pulpotomy, D. Observe, no treatment', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]