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
Proximal walls in a class I tooth preparation for amalgam should 
Select and explain. 
A. Converge occlusally, B. Diverge occlusally, C. Remain straight, D. Rounded
B: Diverge occlusally
Answer: B: Diverge occlusally 
Explanation: None