Diatoms/Diatomaceous earth belong to class

Options

A. Xanthophyceae
B. Bacillariophyceae
C. Phaeophyceae
D. Chlorphyceae.

Answer

To determine the class to which diatoms or diatomaceous earth belong, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Diatoms**: Understand that diatoms are a type of algae commonly found in aquatic environments, particularly in oceans. They are known for their unique cell walls made of silica.

2. **Review the Options**: The options given are:
- Xanthophyce
- Bacillariophyce
- Pheophyce
- Chlorophyce

3. **Analyze Each Option**:
- **Xanthophyce**: This class includes yellow-green algae. Since diatoms are not yellow-green algae, this option is incorrect.
- **Bacillariophyce**: This class is specifically known for diatoms. Since diatoms are classified under this group, this option is likely correct.
- **Pheophyce**: This class includes brown algae. Diatoms are not brown algae, so this option is incorrect.
- **Chlorophyce**: This class includes green algae. Diatoms do not belong to this group, making this option incorrect as well.

4. **Conclusion**: Based on the analysis, the correct class for diatoms or diatomaceous earth is **Bacillariophyce**.

### Final Answer:
Diatoms/Diatomaceous earth belong to the class **Bacillariophyce**.

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