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
In peripheral nerve block, which of the following
local anesthetics has the longest duration of
action?	(OR)
Which of the following local anesthetic agent would be preferred in prolonged surgical procedures? 
Select and explain. 
A. Bupivacaine, B. Cocaine, C. Lignocaine, D. Prilocaine
A: Bupivacaine
Answer: A: Bupivacaine 
Explanation: None