Assertion : The Golgi apparatus mainly performs the function of packaging materials.
Reason : Materials to be packed in the from of vesicles from the ER fuse with trans face of the Golgi apparatus.

Options

A. If both assertion and reason are true amnd 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.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that the Golgi apparatus mainly performs the function of packaging materials. This is indeed true. The Golgi apparatus is known for its role in modifying, sorting, and packaging proteins and lipids that have been synthesized in the endoplasmic reticulum (ER).

2. **Understanding the Reason**: The reason given is that materials to be packed in the form of vesicles from the endoplasmic reticulum fuse with the trans face of the Golgi apparatus. This statement needs to be evaluated for its accuracy.

3. **Function of the Golgi Apparatus**: The Golgi apparatus receives materials from the ER. The side of the Golgi apparatus that faces the ER is known as the cis face, while the side that faces the cytoplasm is known as the trans face.

4. **Correct Fusion Point**: The materials (in vesicles) from the ER actually fuse with the cis face of the Golgi apparatus, not the trans face. This is a critical point because it directly affects the validity of the reason provided.

5. **Conclusion**: Since the assertion is true (the Golgi apparatus does package materials) and the reason is false (the fusion occurs at the cis face, not the trans face), we conclude that the assertion is true, but the reason is false.

6. **Final Answer**: Therefore, the correct option is that the assertion is true, but the reason is false.

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