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': 'Fluoride recharging of a glass ionomer cement restoration is more effective by which of the following agents? \nSelect and explain. \nA. 0.02% NaF solution for 2-3 minutes, B. 0.02% NaF solution for 2-5 minutes, C. 1.23% APF solution for 4-5 minutes, D. 1.23% APF solution for 2-3 minutes', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The ability of a restorative material to be recharged and serve as a fluoride reservoir depends on the type and permeability of the material, the frequency of fluoride exposure, and the concentration\xa0of\xa0the\xa0fluoridating\xa0agent.\xa0For\xa0example,\xa0recharging\xa0is more\xa0effective\xa0by\xa0acidic\xa0fluoridating\xa0agents\xa0such\xa0as\xa0APF.\nRef: Phillip’s Science of Dental Materials ed 12 pg 334', 'role': 'assistant'}]