Assertion :- Kinetochore is essential for cell division.
Reason :- Kinetochores serve as the sites of attachment of spindle fibres to the chromosome.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Kinetochore is essential for cell division." To analyze this, we need to recall the role of kinetochores during cell division.

2. **Role of Kinetochores**: Kinetochores are protein structures located on the centromere of chromosomes. They play a crucial role during cell division, particularly during mitosis and meiosis, by providing a point of attachment for spindle fibers.

3. **Understanding the Reason**: The reason states that "Kinetochores serve as the sites of attachment of spindle fibres to the chromosome." This is a factual statement about the function of kinetochores.

4. **Connecting Assertion and Reason**: Since kinetochores are indeed essential for the proper attachment of spindle fibers to chromosomes, and since spindle fibers are necessary for the movement of chromosomes during cell division, the assertion is supported by the reason.

5. **Conclusion**: Both the assertion and the reason are true, and the reason correctly explains why the assertion is true. Therefore, the correct conclusion is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

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

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