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
Borders of major connectors adjacent to gingival crevices, should be no closer to the crevice
than? 
Select and explain. 
A. 1-2 mm, B. 2-3 mm, C. 3-6 mm, D. 7-10 mm
C: 3-6 mm
Answer: C: 3-6 mm 
Explanation: In maxillary arch, border of major connector must be no closer than 6 mm to gingival crevices of teeth.
In mandibular arch, border of major connector must be no closer than 3 mm to gingival crevices of teeth.