This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Breathing Systems, Subject name: Anaesthesia
[{'content': "Spontaneous breathing circuit used in children is - \nSelect and explain. \nA. Jackson Rees modification of Ayre's T piece, B. Mapleson A or Magill's circuit, C. Mapleson C or water's to & fro canister, D. Bain's circuit", 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Jackson Rees modification of Ayre's T piece o Repeat from previous sessions", 'role': 'assistant'}]