_____is a product of meiosis.

Options

A. Megaspore mother cell
B. Microspore mother cell
C. Primary endosperm nucleus
D. Megaspore

Explanation

**Step-by-Step Solution:**

1. **Understanding Meiosis**: Meiosis is a type of cell division that reduces the chromosome number by half. It occurs in organisms that reproduce sexually and is essential for the formation of gametes (sperm and eggs).

2. **Chromosome Number**: In meiosis, a diploid cell (2N) undergoes division to produce haploid cells (N). For example, if a diploid cell has 10 chromosomes (2N = 10), after meiosis, it will produce four haploid cells, each with 5 chromosomes (N = 5).

3. **Identifying the Product of Meiosis**: The products of meiosis are typically gametes or spores. In plants, meiosis leads to the formation of spores, which can develop into gametophytes.

4. **Analyzing the Options**: The options given are:
- Megaspore mother cell
- Microspore mother cell
- Primary endosperm nucleus
- Megaspore

5. **Choosing the Correct Answer**: Among the options, the megaspore is a product of meiosis. The megaspore is a haploid cell that arises from the meiotic division of the megaspore mother cell.

6. **Conclusion**: Therefore, the correct answer to the question "_____ is a product of meiosis" is **megaspore**.

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