Which is known as Pond Scum/mermaids tresses?

Options

A. Ulothrix
B. Nostoc
C. Spirogyra
D. Anabaena

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the organism known as "Pond Scum" or "Mermaid's Tresses".

2. **Identifying the Options**: The provided options are:
- Eulothrix
- Nostoc
- Spirogyra
- Anabaena

3. **Analyzing the Options**:
- **Eulothrix**: This is a type of green algae, but it is not commonly referred to as pond scum or mermaid's tresses.
- **Nostoc**: This is a genus of cyanobacteria (blue-green algae) that forms gelatinous colonies, but it is not known by the names in question.
- **Spirogyra**: This is a filamentous green algae that is often found in freshwater environments. It has spiral-shaped chloroplasts and can form large masses in water bodies, leading to its common names.
- **Anabaena**: This is another type of cyanobacteria, known for its nitrogen-fixing capabilities, but it does not go by the names mentioned.

4. **Identifying the Correct Answer**: Based on the characteristics and common names, Spirogyra is the organism that is known as "Pond Scum" or "Mermaid's Tresses".

5. **Conclusion**: The correct answer to the question is **Spirogyra**.

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