Assertion :- Anton Von Leeuwenhoek first saw and described a live cell.
Reason:- Robert Brown discovered nucleus.

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

To analyze the given question, we need to evaluate both the assertion and the reason provided.

### Step 1: Evaluate the Assertion
- **Assertion**: Anton Von Leeuwenhoek first saw and described a live cell.
- **Explanation**: Anton Van Leeuwenhoek is indeed credited with the discovery of live cells. He was the first to observe and describe microorganisms using a microscope he developed in the 17th century. This statement is true.

### Step 2: Evaluate the Reason
- **Reason**: Robert Brown discovered the nucleus.
- **Explanation**: Robert Brown, in the early 19th century, did discover the nucleus in plant cells. This statement is also true.

### Step 3: Determine the Relationship
- Now we need to analyze the relationship between the assertion and the reason:
- The assertion talks about Leeuwenhoek's discovery of live cells, while the reason discusses Brown's discovery of the nucleus. Although both statements are true, the reason does not explain or relate to the assertion. Therefore, the reason is not a correct explanation of the assertion.

### Step 4: Conclusion
- Based on the evaluation:
- Both the assertion and the reason are true.
- The reason is not a correct explanation of the assertion.

### Final Answer
- The correct option is: **Both assertion and reason are true, and reason is not a correct explanation of assertion.**

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