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
Metalloprotienases are used in which stage of the amelogenesis: 
Select and explain. 
A. Organising, B. Formative/ Secretory, C. Protective, D. Desmolytic
B: Formative/ Secretory
Answer: B: Formative/ Secretory 
Explanation: Enamelysin is a member of the matrix metalloproteinase family, and its mRNA has been cloned from pig, human, cow, and mouse. Enamelysin is secreted into the enamel matrix during the secretory stage through transition stage of enamel development