Earthworms breathe through their

Options

A. skin
B. gills
C. lungs
D. stomata

Explanation

**Step-by-Step Solution:**

1. **Understanding Breathing**: Breathing is the process of exchanging gases, specifically oxygen (O2) from the atmosphere and carbon dioxide (CO2) produced by the cells in the body.

2. **Identifying Breathing Organs**: Different organisms have different organs for breathing. For example:
- Fish have gills.
- Mammals, including humans, have lungs.
- Plants have stomata for gas exchange.

3. **Breathing in Earthworms**: Earthworms do not have lungs or gills. Instead, they breathe through their skin.

4. **Role of Moist Skin**: The skin of the earthworm must remain moist for effective gas exchange. Oxygen from the atmosphere can dissolve in moisture on the skin and then diffuse into the bloodstream of the earthworm.

5. **Gas Exchange Process**: As oxygen enters the earthworm's body, carbon dioxide produced by its cells diffuses out through the skin back into the atmosphere.

6. **Conclusion**: Therefore, the correct answer to the question "Earthworms breathe through their" is their skin.

**Final Answer**: Earthworms breathe through their skin.

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