The most muscular part of the alimentary canal of earthworm is -

Options

A. Crop
B. Stomach
C. Gizzard
D. Intestine

Answer

To answer the question regarding the most muscular part of the alimentary canal of an earthworm, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Alimentary Canal**: The alimentary canal of an earthworm consists of several parts, including the mouth, pharynx, esophagus, crop, gizzard, intestine, and anus. Each part has a specific function in the digestion process.

2. **Identifying the Parts**: Among the options provided, we need to identify the roles of the crop, stomach, and gizzard:
- **Crop**: This is primarily a storage area for food. It does not have significant muscular action and does not grind food.
- **Stomach**: While it is involved in digestion, it is not the most muscular part of the alimentary canal.
- **Gizzard**: This is a thick, muscular part of the alimentary canal. Its primary function is to grind food into smaller particles, making it easier for digestion.

3. **Analyzing the Functions**: The gizzard's muscular walls allow it to effectively grind food, which is essential for the earthworm's digestion. This grinding process is crucial as it breaks down complex food materials into simpler forms that can be easily digested in the intestine.

4. **Conclusion**: Based on the functions and characteristics of the parts of the alimentary canal, we conclude that the gizzard is the most muscular part of the alimentary canal of the earthworm.

### Final Answer:
The most muscular part of the alimentary canal of the earthworm is the **gizzard**.

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