Earthworms moves on smooth surface with the help of 

Options

A. setae
B. mouth as sucker
C. it do not move on smooth surface
D. suckers

Answer

To answer the question "Earthworms move on smooth surfaces with the help of," we need to analyze the options provided and understand the anatomy and movement mechanism of earthworms.

### Step-by-Step Solution:

1. **Understanding Earthworm Movement**:
- Earthworms belong to the phylum Annelida and are known for their segmented bodies. They can move through various surfaces, including smooth ones.

2. **Analyzing the Options**:
- **Option 1: Setae**: Setae are small bristle-like structures found on the body of earthworms. They help in gripping the soil or rough surfaces, but they are not effective on smooth surfaces.
- **Option 2: Mouth as Sucker**: Earthworms can use their mouth to attach to surfaces. This allows them to anchor themselves and then push their bodies forward, effectively moving on smooth surfaces.
- **Option 3: Do Not Move on Smooth Surface**: This option is incorrect because earthworms can indeed move on smooth surfaces, albeit with a different mechanism than on rough surfaces.

3. **Conclusion**:
- The correct answer is that earthworms move on smooth surfaces with the help of their mouth acting as a sucker. This allows them to attach and slide forward.

### Final Answer:
Earthworms move on smooth surfaces with the help of their mouth acting as a sucker.

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