This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Anaesthesia
Which of the following local anesthetics is useful for topical administration only? 
Select and explain. 
A. Procaine, B. Bupivacaine, C. Etidocaine, D. Benzocaine
D: Benzocaine
Answer: D: Benzocaine 
Explanation: .