Unlike other algae, diatoms do not readily decay due to

Options

A. Siliceous wall
B. Mucilaginous wall
C. Water proof cell wall
D. Non-living cells.

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks why diatoms, a type of algae, do not readily decay unlike other algae.

2. **Identifying Key Features of Diatoms**: Diatoms are unicellular organisms that belong to the kingdom Protista. They are known for their unique cell wall structure.

3. **Analyzing the Options**:
- **Silaceous wall**: This refers to the cell wall of diatoms, which is made of silica (SiO2).
- **Mucilaginous wall**: This type of wall is not characteristic of diatoms.
- **Waterproof cell wall**: While diatoms have a protective structure, this term is not specific to their unique composition.
- **Non-living cell**: Diatoms are living organisms, so this option is incorrect.

4. **Determining the Correct Answer**: The silaceous wall of diatoms is composed of silica, which is highly durable and resistant to decay. This structure prevents the breakdown of diatoms after they die, making them less prone to decay compared to other algae.

5. **Conclusion**: Therefore, the correct answer to the question is "silaceous wall," as it is the unique feature that allows diatoms to resist decay.

### Final Answer:
Diatoms do not readily decay due to their **silaceous wall**.

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