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
Shortest acting beta-blocker - 
Select and explain. 
A. Propranolol, B. Esmolol, C. Timolol, D. Atenolol
B: Esmolol
Answer: B: Esmolol 
Explanation: Ans. is 'b' i.e., Esmolol o Shortest acting b-blocker - Esmololo Longest acting b-blocker - Nodalol