Egg case in earthworms is formed by the secretion of a material which is secreted from

Options

A. peristomium
B. Prostomium
C. Clitellar region
D. Post-clitellar region

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where the egg case (cocoon) in earthworms is formed and which part of the earthworm secretes the material for this formation.

2. **Identifying the Options**: The options provided are:
- Peristomium
- Prostomium
- Clitellar region
- Post-sitellar region

3. **Analyzing Each Option**:
- **Peristomium**: This is the first segment of the earthworm, located at the head. It does not play a role in reproduction, so this option is incorrect.
- **Prostomium**: This is an extension of the peristomium and is also located at the head. It is not involved in reproduction, making this option incorrect as well.
- **Clitellar Region**: This region is located between the 14th and 16th segments of the earthworm. It contains glandular tissue that secretes a viscous fluid, which is crucial for forming the egg case (cocoon). This option is likely correct.
- **Post-sitellar Region**: This region is located after the clitellar region and does not contribute to the formation of the egg case, making this option incorrect.

4. **Conclusion**: The correct answer is the **Clitellar Region**, as it is responsible for secreting the viscous fluid that forms the egg case (cocoon) in earthworms.

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