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: Radiology
[{'content': 'The best method to reduce radiation caries is application of \nSelect and explain. \nA. 0.5% neutral sodium fluoride gel, B. 1% neutral sodium fluoride gel, C. 0.5% stannous fluoride gel, D. 1% stannous fluoride gel', 'role': 'user'}, {'content': "Answer: B \nExplanation: The best method to reduce radiation caries is daily application of a viscous topical 1% neutral sodium fluoride gel in custom-made applicator trays. The best results are achieved from a combination of restorative dental procedures, excellent oral hygiene, a diet restricted in cariogenic foods, and topical applications of sodium fluoride. Patient cooperation in maintaining oral hygiene is extremely important because radiation caries is a lifelong threat. Teeth with gross caries or periodontal involvement are often extracted before irradiation.\nKey Concept:\nThe best method to reduce radiation caries is daily application of a viscous topical 1% neutral sodium fluoride gel in custom-made applicator trays.\nWhite and Pharoah's Oral\xa0Radiology Principles and Interpretation 8th edition", 'role': 'assistant'}]