This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Local and Regional Anesthesia), Subject name: Anaesthesia
Longest acting local anaesthetic drug is? 
Select and explain. 
A. Procaine, B. Prilocaine, C. Lignocaine, D. Bupivacaine
D: Bupivacaine
Answer: D: Bupivacaine 
Explanation: Ans. (d) BupivacaineRef: Morgan's Anaesthesiology 4/e, p 269