Generally red algae do not form:-

Options

A. Zoospore
B. Non-motile spore
C. Non-motile gamete
D. None of these

Answer

**Step-by-Step Solution:**

1. **Identify the Type of Algae**: Red algae belong to the class Rhodophyceae. This classification is crucial for understanding their reproductive methods.

2. **Understand the Color of Red Algae**: The red color of red algae is primarily due to the pigment R-phycoerythrin. This pigment is significant in distinguishing red algae from other types of algae.

3. **Reproductive Methods in Red Algae**:
- **Vegetative Reproduction**: This usually occurs through fragmentation.
- **Asexual Reproduction**: Red algae reproduce asexually through non-motile spores.
- **Sexual Reproduction**: This occurs through non-motile gametes.

4. **Analyze the Options Given**:
- **Zoospore**: Typically found in green and brown algae, where asexual reproduction occurs through motile zoospores. Red algae do not form zoospores.
- **Non-motile Spore**: This is a method of asexual reproduction in red algae, so they do form non-motile spores.
- **Non-motile Gamete**: This is a method of sexual reproduction in red algae, so they do form non-motile gametes.
- **None of These**: This option implies that all previous statements are incorrect, which is not the case.

5. **Conclusion**: The only option that red algae do not form is **zoospore**. Therefore, the correct answer is option one: zoospore.

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