Inhibitory neurotransmitter is

Options

A. Norepinephrine
B. Epinephrine
C. GABA
D. More than one option is correct

Answer

**Step-by-Step Solution:**

1. **Understanding Neurotransmitters:**
- Neurotransmitters are chemical messengers that transmit signals across a synapse from one neuron to another. They are released from the axon terminals of neurons.

2. **Types of Neurotransmitters:**
- Neurotransmitters can be classified into two main types:
- **Excitatory neurotransmitters**: These increase the likelihood of the firing action potential in the receiving neuron.
- **Inhibitory neurotransmitters**: These decrease the likelihood of the firing action potential in the receiving neuron.

3. **Identifying Inhibitory Neurotransmitters:**
- The question specifically asks for inhibitory neurotransmitters. Inhibitory neurotransmitters function to inhibit or decrease the activity of neurons.
- A well-known inhibitory neurotransmitter is **GABA (Gamma-Aminobutyric Acid)**, which plays a crucial role in reducing neuronal excitability throughout the nervous system.

4. **Evaluating the Options:**
- **Option 1: Norepinephrine** - This is primarily an excitatory neurotransmitter.
- **Option 2: Epinephrine** - This is also an excitatory neurotransmitter.
- **Option 3: GABA** - This is an inhibitory neurotransmitter.
- **Option 4: More than one option is correct** - Since only GABA is inhibitory, this option is incorrect.

5. **Conclusion:**
- The only correct answer to the question "Inhibitory neurotransmitter is" is **GABA**.

**Final Answer: GABA (Gamma-Aminobutyric Acid)**

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