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
Matrix vesicles 
Select and explain. 
A. Are found in mantle dentin, B. Contain collagen, C. Produce alkaline phosphatase, D. Inhibit mineralization
A: Are found in mantle dentin
Answer: A: Are found in mantle dentin 
Explanation: None