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
Flumazenil is: 
Select and explain. 
A. Opiate antagonist, B. Diazepam antagonist, C. Opiate agonist, D. Antianginal drug
B: Diazepam antagonist
Answer: B: Diazepam antagonist 
Explanation: Diazepam antagonist