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
Angulation of a periodontal instrument refers to the 
Select and explain. 
A. angle between the face of the blade and the shank, B. angle between the shank and the shaft, C. angle between the face of the blade and the tooth surface, D. angle between the shank and the tooth surface
C: angle between the face of the blade and the tooth surface
Answer: C: angle between the face of the blade and the tooth surface 
Explanation: None