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': 'CADIA System is used to check? \nSelect and explain. \nA. Progression of Periodontal Disease, B. Mobility of Teeth, C. Furcation Involvement, D. Bleeding Sites', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]