This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
Duration of action of flumazenil is: 
Select and explain. 
A. 5 minute, B. 10 minute, C. 20 minute, D. 1-2 hours
D: 1-2 hours
Answer: D: 1-2 hours 
Explanation: Flumazenil is absorbed orally ;oral bioavailability is ~16% but its not used orally .On I.v .injection ,action of flumazenil stas in seconds &last for 1-2 hours ;elimination t1/2 is 1 hour due to rapid metabolism. REF: KD Tripathi 8th ed.