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: Surgery
Placement of very sharp pointed instrument into the periodontium to extrude tooth out of the socket, this is called: 
Select and explain. 
A. Lever principle., B. Wedge principle., C. Wheel and axle principle., D. None.
B: Wedge principle.
Answer: B: Wedge principle. 
Explanation: None