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 most common indication for tracheostomy is: 
Select and explain. 
A. Laryngeal diphtheria, B. Foreign body aspiration, C. Carcinoma, D. Asthma
B: Foreign body aspiration
Answer: B: Foreign body aspiration 
Explanation: Historically, the main indication for a tracheostomy was to bypass upper airway obstruction caused by a foreign body or infection, paicularly diphtheria. Nowadays upper airway obstruction is the least common indicator for tracheostomy. Almost two thirds of tracheostomies are currently performed on intubated intensive care patients, mainly to aid removal of secretions from the distal tracheobronchial tree and to facilitate weaning from distal tracheobronchial tree in acute respiratory failure and prolonged ventilation