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': 'Anti-calculus agent in toothpaste is \nSelect and explain. \nA. Cocoamidopropyl, B. Pyrophosphate, C. Fluoride, D. Lauryl sulphate', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]