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': 'Cementum formation is more rapid in: \nSelect and explain. \nA. Apical portion., B. Coronal portion., C. Even over the entire root., D. At furcation.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]