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
In ceramic restoration, which can be used 
Select and explain. 
A. 1.23% APF, B. 8% SnF2, C. 6% SnF2, D. 2% NaF
D: 2% NaF
Answer: D: 2% NaF 
Explanation: None