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
Best anaesthetic agent for out patient anasthesia is 
Select and explain. 
A. Fentanyl, B. Morphine, C. Alfentanyl, D. Penthidine
C: Alfentanyl
Answer: C: Alfentanyl 
Explanation: C i.e. Alfentanyl