In Earthworm, cocoon is formed by

Options

A. Epidermal muscles
B. Setae
C. Cuticle
D. Clitellum

Answer

To answer the question "In Earthworm, cocoon is formed by?", we will follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: We need to identify which structure in the earthworm is responsible for forming the cocoon during reproduction.

2. **Identifying the Options**: The options provided are:
- Epidermal muscles
- Setae
- Cuticle
- Clitellum

3. **Analyzing Each Option**:
- **Epidermal Muscles**: These muscles are present throughout the body of the earthworm but do not play a role in cocoon formation.
- **Setae**: These are small bristle-like structures found on each segment of the earthworm, except for the first, last, and clitellum segments. They are primarily used for locomotion and do not contribute to cocoon formation.
- **Cuticle**: This is the outer body lining of the earthworm, which serves as protection but does not form the cocoon.
- **Clitellum**: This is a specialized glandular structure found in segments 14 to 17 of the earthworm. During sexual maturity, the clitellum secretes a viscous fluid that helps form the cocoon for laying eggs.

4. **Conclusion**: Based on the analysis, the correct answer is **Clitellum**, as it is the structure responsible for the formation of the cocoon in earthworms.

### Final Answer:
The cocoon in earthworms is formed by the **Clitellum**.

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