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: ENT
The Myer-Cotton grading system is used for: 
Select and explain. 
A. Subglottic stenosis, B. Tonsillitis, C. Sinisitis, D. None of the above
A: Subglottic stenosis
Answer: A: Subglottic stenosis 
Explanation: The Myer-Cotton grading system describes the severity of stenosis according to the percentage of subglottic stenosis present. The percentage is calculated by measuring the largest sized endotracheal tube that can be passed through the subglottis and comparing this with the age-appropriate tube size for the child