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
Secondary peripheral seal area in mandible is provided by: 
Select and explain. 
A. Buccal shelf, B. Anterior lingual border, C. Retromolar pad, D. Crest of the ridge
B: Anterior lingual border
Answer: B: Anterior lingual border 
Explanation: None