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
Vaccine for caries is based on which immunoglobulin 
Select and explain. 
A. IgG, B. IgA, C. IgE, D. IgM
B: IgA
Answer: B: IgA 
Explanation: None