Assertion :- Schwann cells are present in myelinated & unmyelinated axon.
Reason:- Schwann cell has functions of myelinogenes in PNS & function as packaging cell in autonomous neural system and somatic neural system.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

To solve the question, we will analyze the assertion and reason provided, and then determine the correct relationship between them.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Schwann cells are present in myelinated and unmyelinated axons."
- Schwann cells are a type of glial cell in the peripheral nervous system (PNS) that are responsible for the formation of the myelin sheath around myelinated axons. They also surround unmyelinated axons, providing support and insulation.

2. **Understanding the Reason**:
- The reason states that "Schwann cells have functions of myelinogenesis in PNS and function as packaging cells in the autonomic neural system and somatic neural system."
- Myelinogenesis refers to the process of forming the myelin sheath. Schwann cells indeed play a crucial role in this process for myelinated axons. Additionally, they provide structural support (packaging) for both autonomic and somatic nervous systems.

3. **Evaluating the Truth of the Statements**:
- Both the assertion and reason are true. Schwann cells are present in both types of axons (myelinated and unmyelinated), and they perform the functions described in the reason.

4. **Determining the Relationship**:
- The reason correctly explains the assertion. Since Schwann cells are responsible for myelination and also serve as packaging cells, the reason supports the assertion.

5. **Conclusion**:
- Therefore, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, and the reason is the correct explanation of the assertion.