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
All of the following are methods for improving oxygenation using a ventilator, except: 
Select and explain. 
A. High frequency ventilation, B. Low tidal volume high PEEP, C. Extracorporeal membrane oxygenation (ECMO), D. Prone ventilation
A: High frequency ventilation
Answer: A: High frequency ventilation 
Explanation: Ans. a. High frequency ventilation