Which statement is true?

Options

A. In PNS, only non-myelinated neuron are found.
B. In CNS, myelinated and non-myelinated neurons are found.
C. In PNS, myelinated and non-myelinated neurons are found.
D. Both B and C

Answer

To determine which statement is true regarding the nervous system, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Analyze the First Statement**:
- The first statement claims that "in the peripheral nervous system only non-myelinated neurons are found."
- This statement is **false** because the peripheral nervous system (PNS) contains both myelinated and non-myelinated neurons. Myelinated neurons are present in the PNS, particularly in the form of Schwann cells that wrap around the axons.

**Hint**: Remember that both types of neurons can exist in the PNS.

2. **Analyze the Second Statement**:
- The second statement states that "myelinated and non-myelinated neurons are found in the central nervous system."
- This statement is **true**. The central nervous system (CNS) comprises both types of neurons. Myelinated neurons are present, which are crucial for rapid signal conduction, while non-myelinated neurons are also part of the CNS.

**Hint**: Focus on the role of myelination in speeding up signal transmission.

3. **Analyze the Third Statement**:
- The third statement mentions that "in the peripheral nervous system myelinated and non-myelinated neurons are found."
- This statement is also **true**. As previously mentioned, the PNS includes both myelinated and non-myelinated neurons.

**Hint**: Recall that the presence of myelinated neurons in the PNS is significant for certain functions.

4. **Analyze the Fourth Statement**:
- The fourth statement claims "both B and C."
- Since both statements B and C are true, this statement is also **true**.

**Hint**: If two statements are true, the option that includes both is also true.

### Conclusion:
The correct answer is **option 4**, which states that both B and C are true.