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
Pit and fissure sealants are bound to tooth surface by 
Select and explain. 
A. Chemical bond, B. Mechanical Retention, C. Adhesive bond, D. Chemical and mechanical bond
B: Mechanical Retention
Answer: B: Mechanical Retention 
Explanation: None