Spirogyra belongs to the class

Options

A. Rhodophyceae
B. Cyanophyceae
C. Xanthophyceae
D. Chlorophyceae.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about Spirogyra, which is a type of algae.

2. **Classify the Algae**: Spirogyra is known for its filamentous structure and is commonly referred to as "pond silk" or "water silk".

3. **Examine the Characteristics**: It is important to note that Spirogyra has a unique feature - its chloroplasts are spiral or helical in shape.

4. **Review the Options**: The options provided are:
- Rhodophyce (Red algae)
- Cyanophyce (Blue-green algae)
- Xenophyce (Yellow algae)
- Chlorophyce (Green algae)

5. **Determine the Correct Class**: Since Spirogyra is characterized as a green algae due to its chlorophyll content and its classification under the green algae group, it belongs to the class Chlorophyceae.

6. **Conclude the Answer**: Therefore, the correct answer is that Spirogyra belongs to the class **Chlorophyceae**.

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