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
A curvature of gingiva towards the roots found in the middle of the interproximal area between molars is termed as 
Select and explain. 
A. Col, B. Self cleansing area, C. Interproximal embrasure, D. Cervix
A: Col
Answer: A: Col 
Explanation: None