Which of the following is a component of rapid sequence induction of anaesthesia?

Rapid sequence induction(RSI) is a technique of choice in the establishment of a secure airway in the emergency depament. The process is broken into six phases which is to be carried out in order. They are pre oxygenation, preparation, pre medication, paralysis and sedation, passage of tube and post intubation care. Pre oxygenation is a vital pa of RSI. As it allows the development of an oxygen reserve within the alveoli of the lungs and also within the circulation and tissues by displacing nitrogen with oxygen. Pre oxygenation is done by breathing 100% oxygen a tight fitting mask for 3 minutes. Ref: Oxford Desk Reference - Major Trauma By Jason Smith, Page 50 ; Miller's Anesthesia, 7th Edition, Chapter 73 - Anesthesia and Prehospital Emergency and Trauma Care