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
Why a hard surface is necessary for a die stone: 
Select and explain. 
A. To prevent breakage of die., B. To prevent water absorption., C. To make surface abrasion resistant., D. To easy removal of wax pattern.
C: To make surface abrasion resistant.
Answer: C: To make surface abrasion resistant. 
Explanation: None