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
Indications for mucogingival surgery include the following except 
Select and explain. 
A. A shallow vestibule, B. Insufficient attached gingiva, C. Infrabony pockets, D. A high frenum attachment
C: Infrabony pockets
Answer: C: Infrabony pockets 
Explanation: None