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': 'Gracey curettes are area specific instruments because: \nSelect and explain. \nA. They are used in the specific areas of the US, B. They adapt to specific areas of the tooth or root, C. They have more than one angle per cutting edge, D. They are used for root planning', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]