Benzodiazepine (BZD) receptor antagonist is -

Ans. is 'd' i.e., Flumazenil o Flumazenil is a benzodiazepene analogue which competes with BZD agonists as well as inverse agonists for the BZD receptor and reverses their depressant or stimulant effects respectively.o It also antagonizes the action of Zolpidem, Zopiclone and Zopeplon as these drugs also act on BZD site.