**Core Concept**
Benzodiazepines are a class of psychoactive drugs that enhance the effect of the neurotransmitter gamma-aminobutyric acid (GABA) at the GABA_A receptor, resulting in sedative, hypnotic, anxiolytic, anticonvulsant, and muscle relaxant properties. To counteract these effects, a specific antagonist is required to reverse the action of benzodiazepines.

**Why the Correct Answer is Right**
Flumazenil is a selective, competitive antagonist of the benzodiazepine site on the GABA_A receptor. It works by binding to the benzodiazepine receptor and preventing the action of benzodiazepines, thereby reversing their effects. Flumazenil is used clinically to reverse excessive sedation, respiratory depression, or other adverse effects caused by benzodiazepines. It is also used to diagnose benzodiazepine overdose or dependence.

**Why Each Wrong Option is Incorrect**
**Option A:** None provided.
**Option B:** None provided.
**Option C:** None provided.

**Clinical Pearl / High-Yield Fact**
Flumazenil has a relatively short duration of action (about 1 hour) and may not be effective against long-acting benzodiazepines. Its use should be carefully considered in patients with a history of benzodiazepine dependence or seizure disorders.

**Correct Answer:** C. Flumazenil.