Which of the following is the appropriate reversal agent for benzodiazepines?

Flumazenil is the appropriate reversal agent for benzodiazepines. This medication specifically acts as a competitive antagonist at the benzodiazepine site of the GABA-A receptor, effectively reversing the sedative and respiratory depressant effects caused by benzodiazepines. When administered, flumazenil can rapidly reverse the effects of benzodiazepine overdose, making it a vital tool in emergency medicine for situations where patients may present with excessive sedation or altered consciousness due to benzodiazepine use.

In comparison, acetylcysteine is utilized as an antidote for acetaminophen toxicity, while naloxone is the specific reversal agent for opioid overdoses. Protamine sulfate is used to reverse the anticoagulant effects of heparin. Thus, flumazenil stands out as the specific agent designed to counter the effects of benzodiazepines, making it the correct choice in this context.