In Pheretima, which nephridia are present?

Options

A. Protonephridia
B. Coelom duct
C. Micro-metanephridia
D. Solenocytes

Answer

To answer the question regarding which nephridia are present in Pheretima, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the context**: Pheretima is a genus of earthworms, and they have a specific type of excretory system.

2. **Identify the types of nephridia**: There are several types of nephridia mentioned:
- Protonephridia
- Coelom duct
- Micrometanephridia
- Solenocytes

3. **Eliminate incorrect options**:
- **Solenocytes**: These are flame cells found in platyhelminths (flatworms) and are not present in Pheretima. Therefore, this option is incorrect.
- **Protonephridia**: This type of nephridia is also not found in Pheretima. Thus, this option is incorrect.
- **Coelom duct**: While coelom ducts are associated with the body cavity in some organisms, they are not the primary excretory structures in Pheretima. Hence, this option is also incorrect.

4. **Identify the correct option**: The remaining option is **Micrometanephridia**. These are indeed the type of nephridia present in Pheretima. They are smaller in size compared to metanephridia and are adapted for the excretory function in these earthworms.

5. **Conclusion**: Therefore, the correct answer to the question is that Pheretima possesses **Micrometanephridia**.

### Final Answer:
Pheretima has **Micrometanephridia**.