This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autonomic nervous system, Subject name: Pharmacology
Drug used in aneliorative test for Myasthenia gravis is 
Select and explain. 
A. Physostigmine, B. Edrophonium, C. Tacrine, D. Pyridostigmine
B: Edrophonium
Answer: B: Edrophonium 
Explanation: Drug used in amellorative test (tensilon test) for myasthena gavis is edrophonium. It is a cholinergic drug and can be used for diagnosis of myasthenia gravis becaise of its sho duration of action (10-30 min) Ref-KDT 6/e p104