Assertion : Chromosomes are thread-like structures present in the nucleus
Reason : In bacteria, chromosomes is not found as there is no nucleus

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

### Step-by-Step Solution:

1. **Understand the Assertion**: The assertion states that "Chromosomes are thread-like structures present in the nucleus." This statement is true. Chromosomes are indeed thread-like structures that contain genetic information and are located in the nucleus of eukaryotic cells.

2. **Understand the Reason**: The reason provided is "In bacteria, chromosomes are not found as there is no nucleus." This statement is misleading. While it is true that bacteria do not have a nucleus (as they are prokaryotic cells), they do have chromosomes. Bacterial chromosomes are typically circular and are located in the cytoplasm, not in a nucleus.

3. **Evaluate the Truth of Each Statement**:
- The assertion is true.
- The reason is false because it incorrectly states that chromosomes are not found in bacteria.

4. **Determine the Relationship Between Assertion and Reason**: Since the assertion is true and the reason is false, the reason does not correctly explain the assertion.

5. **Select the Correct Option**: Based on the evaluation, the correct option is that the assertion is true but the reason is false.

### Final Answer:
The correct answer is: **Assertion is true, but Reason is false.**

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