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': 'Immediately following a traumatic injury to upper central incisor, pulp testing is negative. Treatment of choice would be: \nSelect and explain. \nA. Pulpectomy, B. Pulpotomy, C. Apexification, D. None of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: A negative response, however, is not reliable evidence of pulp death because some teeth that give such a response soon after the injury may recover vitality after a time.', 'role': 'assistant'}]