In pteridophyta, reduction division occurs when :-

Options

A. Prothallus is formed
B. Spores are formed
C. Sex organs are formed
D. Gametes are formed

Answer

### Step-by-Step Solution:

1. **Understanding Pteridophyta**: Pteridophyta, commonly known as ferns, exhibit a life cycle that includes both a haploid (gametophyte) and a diploid (sporophyte) generation.

2. **Identifying Generations**: In the life cycle of pteridophytes, the sporophyte generation is diploid (2N) and produces spores through a process called meiosis (reduction division). The gametophyte generation is haploid (N) and produces gametes.

3. **Meiosis in Pteridophyta**: Reduction division, or meiosis, occurs specifically during the formation of spores. During this process, the diploid sporophyte undergoes meiosis to produce haploid spores.

4. **Formation of Gametes**: The gametes are formed in the haploid gametophyte generation, which arises from the germination of the haploid spores. The formation of gametes does not involve meiosis; instead, it is a process of mitosis.

5. **Conclusion**: Therefore, in pteridophytes, reduction division occurs when spores are formed.

### Final Answer:
In pteridophyta, reduction division occurs when **spores are formed**.

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