common in feather and silk is

Options

A. carbohydrate
B. fats
C. protein
D. nucleic acid

Answer

To determine what is common in feathers and silk, let's analyze the options provided:

1. **Understanding the Composition of Feathers:**
- Feathers are structural features found in birds.
- The primary component of feathers is a protein called **keratin**.

2. **Understanding the Composition of Silk:**
- Silk is produced by silkworms and is obtained from their cocoons.
- The main component of silk is a protein known as **fibroin**.

3. **Comparing the Two:**
- Both feathers and silk are primarily composed of proteins.
- While they are made up of different types of proteins (keratin in feathers and fibroin in silk), the commonality lies in the fact that both are proteins.

4. **Analyzing the Options:**
- **Carbohydrate:** Incorrect. Neither feathers nor silk is made up of carbohydrates.
- **Fats:** Incorrect. Fats are lipids and are not components of feathers or silk.
- **Protein:** Correct. Both feathers and silk are made up of proteins.
- **Nucleic Acid:** Incorrect. Nucleic acids are not structural components of feathers or silk.

5. **Conclusion:**
- The common feature in both feathers and silk is that they are both made up of **proteins**.

### Final Answer:
The common component in feathers and silk is **protein**.

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