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': 'School water fluoridation was first initiated in \nSelect and explain. \nA. Seagrove, North Carolina, B. St. Thomas virgin islands, C. Elk lake, Pennsylvania, D. Pike country, Kentucky', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]