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
For CD fabrication minimum interarch distance needed? 
Select and explain. 
A. 8 to 10 mm, B. 18 to 20 mm, C. 28 to 30 mm, D. 36 to 40 mm
B: 18 to 20 mm
Answer: B: 18 to 20 mm 
Explanation: None