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: Anaesthesia
Most important measure to avoid subglottic edema in children is 
Select and explain. 
A. Use of appropriate size endotracheal tube, B. Lubricating endotracheal tube prior to intubation, C. Administer i.v Lidocaine for all intubations, D. Administer i.v Steroids for all intubations
A: Use of appropriate size endotracheal tube
Answer: A: Use of appropriate size endotracheal tube 
Explanation: Larger outer diameter of endotracheal tube, multiple intubation attempts, children between 1-4 years are risk factors for subglottic edema and croup. So appropriate size endotracheal tube has tube used.