The excretory organ of earthworm are

Options

A. Nephridia
B. Solenocytes
C. Green glands
D. Kidneys

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the excretory organ of earthworms. To answer this, we need to identify the correct organ from the given options.

2. **Analyzing the Options**:
- **Option 1: Nephridia**: This is known to be the excretory organ in earthworms. Nephridia are tube-like structures that help in the removal of waste products from the body.
- **Option 2: Solenocytes**: These are also known as flame cells and are found in lower organisms like platyhelminths (flatworms). They are not present in earthworms.
- **Option 3: Green glands**: Also called antennal glands, these are found in crustaceans like prawns and shrimps, not in earthworms.
- **Option 4: Kidney**: Kidneys are excretory organs found in mammals and larger vertebrates, not in earthworms.

3. **Elimination of Incorrect Options**:
- **Kidney**: Incorrect, as it is specific to mammals.
- **Green glands**: Incorrect, as they are found in crustaceans.
- **Solenocytes**: Incorrect, as they are found in flatworms.

4. **Conclusion**: After analyzing and eliminating the incorrect options, we find that the correct answer is **Nephridia**, which are the excretory organs of earthworms.

### Final Answer:
The excretory organ of earthworms is **Nephridia**.

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