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
True about anaesthesia machine – a) Cylinder is a part of high pressure systemb) O2 flush delivers < 35 litc) O2 flush delivers > 35 litd) Pipeline is a part of low pressure system 
Select and explain. 
A. a, B. bc, C. ad, D. ac
D: ac
Answer: D: ac 
Explanation: There are two sources of gases (O2, N2O & air) for anaesthetic machine :-


Cylinder          → High pressure system
Pipeline source → Intermediate pressure system


Oxygen flush delivers 35-75 liters of oxygen per minute.