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': 'Which is the first study on water fluoridation? \nSelect and explain. \nA. Grand rapids (Michigan) & Muskegon, B. Newberg & Kingston, C. Brantferd & Sarnia, D. Evanston & Park', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]