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
Mapelson system used in children is: 
Select and explain. 
A. Type A, B. Type B, C. Type C, D. Ayers T tube
D: Ayers T tube
Answer: D: Ayers T tube 
Explanation: Ayers T tube