This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: A.N.S., Subject name: Pharmacology
Which of the following is not a carbamate? 
Select and explain. 
A. Physostigmine, B. Neostigmine, C. Edrophonium, D. Pyridostigmine
C: Edrophonium
Answer: C: Edrophonium 
Explanation: Ans. (C) Edrophonium(Ref: KDT 8th/e p116, Katzung 11/e p104)Physostigmine, neostigmine and pyridostigmine are carbamates by chemical nature, whereas edrophonium is an alcohol.