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': 'Soft tooth brush is recommended in periodontal patients because soft bristles are: \nSelect and explain. \nA. More flexible allowing easy access to all areas, B. Less abrasion of tooth structure than hard brush, C. Freying is less with soft bristles, D. None of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]