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': 'Most mature enamel is found at? \nSelect and explain. \nA. Apical region, B. Incisal edge and cusp tip, C. Middle region, D. Cervical region', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]