Assertion : Meiosis produces four genetically dissimilar cells.
Reason : Crossing over or gene exchange takes place in meiosis.

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 "Meiosis produces four genetically dissimilar cells."
- This is true because meiosis is a type of cell division that reduces the chromosome number by half and results in four daughter cells, each with a unique combination of genes.

2. **Understanding the Reason:**
- The reason provided is that "Crossing over or gene exchange takes place in meiosis."
- This is also true. During meiosis, specifically in prophase I, homologous chromosomes undergo crossing over, where segments of DNA are exchanged between them. This process increases genetic diversity.

3. **Connecting the Assertion and Reason:**
- The assertion is supported by the reason. The genetic dissimilarity of the cells produced in meiosis is largely due to the process of crossing over, which creates new combinations of alleles.

4. **Conclusion:**
- Both the assertion and the reason are true, and the reason correctly explains why the assertion is true.

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

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