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
Pungent volatile anesthetic agents are: 
Select and explain. 
A. Halthane, B. Isoflurane, C. Sevoflurane, D. Desflurane
B: Isoflurane
Answer: B: Isoflurane 
Explanation: B i.e. Isoflurane