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
Saliva contains which of the following acts as defence mechanism for prevention of dental caries? 
Select and explain. 
A. Lysozyme, B. Lactoferrin, C. Lactoperoxidase, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: None