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
In a class 1 cavity prepared for silver amalgam is extended to half the distance between the contact area and the fissures and the cusp tip, the direction of the buccal and lingual walls is: 
Select and explain. 
A. Diverging, B. Converging, C. Parallel, D. Independent
B: Converging
Answer: B: Converging 
Explanation: None