Earthworms have

Options

A. Well-developed special sence organs
B. Eyes and ears
C. Receptor cells only
D. Complex sence organs

Answer

### Step-by-Step Solution:

1. **Definition of Earthworms**: Earthworms are terrestrial invertebrates that belong to the phylum Annelida. They have a segmented body structure and are commonly found in soil.

2. **Nervous System**: Earthworms possess a simple nervous system with a nerve cord and a simple brain. This allows them to process sensory information from their environment.

3. **Sensory Organs**: Earthworms do not have complex sense organs like eyes and ears. Instead, they have:
- **Light Receptors**: These help them detect light and dark, which is essential for avoiding predators and finding food.
- **Chemoreceptors**: Their skin is covered with chemoreceptors that help them taste and detect chemicals in their environment.

4. **Vibrational Sensitivity**: Earthworms can sense vibrations in the soil, which helps them detect the presence of predators, such as birds or moles.

5. **Respiration**: Earthworms do not have lungs or a nose. They breathe through their skin, which must remain moist to facilitate gas exchange. They absorb oxygen and release carbon dioxide through their skin.

6. **Conclusion**: Based on the information, earthworms primarily have receptor cells (chemoreceptors and light receptors) that allow them to interact with their environment, making the correct answer to the question that earthworms have receptor cells only.