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
Which index uses calibrated probe for calculus? 
Select and explain. 
A. OHI, B. Marginal line calculus index, C. Calculus severity index, D. Volpe Manhold Index
D: Volpe Manhold Index
Answer: D: Volpe Manhold Index 
Explanation: None