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: Surgery
Which of the anaesthetic agent is maximally metabolized: 
Select and explain. 
A. Methoxyflurane, B. Halothane, C. Nitrous oxide, D. Isoflurane
A: Methoxyflurane
Answer: A: Methoxyflurane 
Explanation: Methoxyflurane is most extensively metabolized. (50%), to liberate very high fluoride.