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
Failure of partial dentures due to poor clasp design can best be avoided by: 
Select and explain. 
A. Using stress breakers, B. Using bar type clasps, C. Altering tooth contours, D. Clasping only those teeth with fairly long crowns and normal bone support
C: Altering tooth contours
Answer: C: Altering tooth contours 
Explanation: None