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': 'The first ADA approved fluoride toothpaste in the year: \nSelect and explain. \nA. 1960, B. 1968, C. 1964, D. 1954', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In 1955, the stannous fluoride dentifrice became the first dentifrice recognized by the Food and Drug Administration (FDA) as an effective tooth decay preventive product.\xa0\nThe first fluoride dentifrice was accepted by American Dental Association (ADA) in 1964. It is called CREST.\n\nEssentials of preventive and community dentistry\nSoben Peter\n5th edition\npage no. 261', 'role': 'assistant'}]