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
The value of C-factor for class IV composite restoration is 
Select and explain. 
A. 0.25, B. 0.5, C. 1, D. 2
B: 0.5
Answer: B: 0.5 
Explanation: None