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
Method of increasing attached gingiva 
Select and explain. 
A. Apical flap, B. Widman flap, C. Undisplaced flap, D. Modified widman flap
A: Apical flap
Answer: A: Apical flap 
Explanation: None