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': 'Following fracture of the root, the reaction to test of pulp vitality may be negative for as long as ………..weeks \nSelect and explain. \nA. 6-8 weeks, B. 10-12 weeks, C. 20-24 weeks, D. 1-2 weeks', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]