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
Any clasp assembly should encircle at Least how much of the abutment tooth? 
Select and explain. 
A. 120, B. 160, C. 180, D. 360
C: 180
Answer: C: 180 
Explanation: None