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: Pharmacology
All of the following are halogenated anaesthetic agents except : 
Select and explain. 
A. Halothane, B. Propofol, C. Enflurane, D. Isoflurane
B: Propofol
Answer: B: Propofol 
Explanation: None