Which is protein in nature

Options

A. Polyethylene
B. Silk and wool
C. Cellulose
D. Terylene

Explanation

### Step-by-Step Solution:

1. **Identify the Options**: The question provides four options: polyethylene, silken wool, cellulose, and ptarylene.

2. **Analyze Each Option**:
- **Polyethylene**: This is a synthetic polymer commonly used in plastics and is not a protein.
- **Silken Wool**: This refers to silk, which is produced by silkworms. It is primarily made up of proteins, specifically fibroin and sericin.
- **Cellulose**: This is a polysaccharide that forms the cell wall of plants and is not a protein.
- **Ptarylene**: This is another synthetic polymer and is not a protein.

3. **Determine the Protein Source**: Among the options, silken wool (silk) is the only one that is protein in nature. Silk is composed of proteins, making it the correct answer.

4. **Conclusion**: The protein in nature from the given options is silken wool.

### Final Answer:
The protein in nature is **silken wool**.

---