This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anaesthetic equipments, Subject name: Anaesthesia
[{'content': 'Circuit of choice for controlled ventilation \nSelect and explain. \nA. Magill circuit, B. Type C, C. Type D, D. Type E', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Bains co-axial system is used in controlled ventilation.Fresh gas flow required to prevent rebreathing is 1.6MV.', 'role': 'assistant'}]