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
Cutting and grinding procedures are predominantly: 
Select and explain. 
A. Two directional, B. Unidirectional, C. Three directional, D. Multidirectional
B: Unidirectional
Answer: B: Unidirectional 
Explanation: None