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
For porcelain fused to metal crown, the porcelain should have? 
Select and explain. 
A. High fusion expansion, B. High fusion temperature, C. Linear coefficient of thermal expansion less than that of metal, D. Linear coefficient of thermal expansion more than that of metal
C: Linear coefficient of thermal expansion less than that of metal
Answer: C: Linear coefficient of thermal expansion less than that of metal 
Explanation: None