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
Glossy smooth margins of a casting are due to: 
Select and explain. 
A. Shrinkage of alloy on cooling, B. Investment breakdown, C. Incomplete wax elimination, D. Incomplete gas elimination
C: Incomplete wax elimination
Answer: C: Incomplete wax elimination 
Explanation: None