________ is rigid layer which is not present in animal cells, but is found in plant cells.

Options

A. Cell wall
B. Cell membrane
C. Plasma membrane
D. Nucleus membrane

Explanation

**Step-by-Step Solution:**

1. **Identify the Rigid Layer**: The question asks for a rigid layer that is not found in animal cells but is present in plant cells.

2. **Consider the Options**: The options provided are cell wall, cell membrane, plasma membrane, and nucleus membrane.

3. **Analyze Each Option**:
- **Cell Membrane/Plasma Membrane**: This is a flexible layer present in both plant and animal cells. It separates the interior of the cell from the external environment.
- **Nucleus Membrane**: Also known as the nuclear membrane, it surrounds the nucleus and is present in both plant and animal cells.
- **Cell Wall**: This is a rigid layer that is found only in plant cells. It provides structural support and protection.

4. **Conclusion**: Since the cell wall is the only option that is not present in animal cells but is found in plant cells, it is the correct answer.

5. **Final Answer**: The answer to the question is "Cell Wall".

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