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
[{'content': "Rebreathing systems are A/E – \nSelect and explain. \nA. To & fro system, B. Circle system, C. Water's system, D. Mapleson F", 'role': 'user'}, {'content': "Answer: D \nExplanation: Closed (rebreathing) circuits are circle system and To and fro (Water's / Mapleson C) system.", 'role': 'assistant'}]