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
If periodontal surgery is necessary in case of horizontal bone toss in upper anterior region. Which of the following procedure is the most appropriate? 
Select and explain. 
A. Papilla preservation flap, B. Widman flap, C. Coronally displaced flap, D. Gingivectomy
A: Papilla preservation flap
Answer: A: Papilla preservation flap 
Explanation: None