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
The first drug used as local anaesthetic is ? 
Select and explain. 
A. Cocaine, B. Prilocaine, C. Procaine, D. Lidocaine
A: Cocaine
Answer: A: Cocaine 
Explanation: Ans. is'a' i.e., CocaineCocaine was the first local anaesthetic used by Carl Koller. It was used for anaesthetizing cornea.