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: Surgery
Which of the following is not a complication of tracheostomy: 
Select and explain. 
A. Surgical emphysema, B. Pneumothorax, C. Carotid artery injury, D. Subglottic stenosis
D: Subglottic stenosis
Answer: D: Subglottic stenosis 
Explanation: None