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': 'Dental floss is used to: \nSelect and explain. \nA. Remove interdental plaque, B. Remove interdental food and debris, C. Massage gums, D. Prevent gingival recession', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]