**Core Concept**
GABA (gamma-aminobutyric acid) transmission is a type of inhibitory neurotransmission in the central nervous system. It plays a crucial role in regulating neuronal excitability, muscle tone, and various physiological processes. GABA acts as an inhibitory neurotransmitter by binding to GABA_A receptors, which are ligand-gated chloride channels.

**Why the Correct Answer is Right**
The correct answer is GABA_A receptors. GABA_A receptors are a type of ionotropic receptor that consists of five subunits (α, β, γ, δ, and ρ). When GABA binds to these receptors, it opens the chloride channel, allowing chloride ions to flow into the neuron, which hyperpolarizes the cell membrane and reduces the likelihood of action potential firing. This mechanism is essential for regulating neuronal excitability and is involved in various physiological processes, including sleep, muscle relaxation, and anxiety.

**Why Each Wrong Option is Incorrect**
**Option A:** GABA_C receptors are not directly involved in the facilitation of GABA transmission. Instead, they are metabotropic receptors that activate G-proteins, which can indirectly modulate GABAergic transmission.

**Option B:** GABA_B receptors are metabotropic receptors that activate G-proteins, which can modulate GABAergic transmission, but they are not directly involved in the facilitation of GABA transmission.

**Option C:** Glycine receptors are also ligand-gated chloride channels, but they are primarily involved in inhibitory neurotransmission in the spinal cord and brainstem, not in the facilitation of GABA transmission.

**Clinical Pearl / High-Yield Fact**
GABA_A receptors are the primary target for benzodiazepines, which enhance GABAergic transmission by increasing the frequency of chloride channel opening. This mechanism is responsible for the anxiolytic, sedative, and muscle relaxant effects of benzodiazepines.

**Correct Answer:** GABA_A receptors.