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
Rebreathing systems are A/E – 
Select and explain. 
A. To & fro system, B. Circle system, C. Water's system, D. Mapleson F
D: Mapleson F
Answer: D: Mapleson F 
Explanation: Closed (rebreathing) circuits are circle system and To and fro (Water's / Mapleson C) system.