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': 'Anesthetic testing is most effective in localizing pain \nSelect and explain. \nA. to a specific tooth., B. to the mandible or maxilla., C. across the midline of the face., D. to a posterior tooth.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]