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: Pharmacology
The short acting anticholinesterase drug is: 
Select and explain. 
A. Edrophonium, B. Demecarium, C. Dyflos, D. Ectothiophate
A: Edrophonium
Answer: A: Edrophonium 
Explanation: None