A mollusc with parapodia is

Options

A. Aplysia
B. Doris
C. Chiton
D. pila

Answer

To solve the question "A mollusc with parapodia is," we need to analyze the options provided and understand the characteristics of each one.

### Step-by-Step Solution:

1. **Understanding Parapodia**:
- Parapodia are fleshy extensions or appendages found on the body of certain mollusks. They are primarily used for locomotion and respiration.

2. **Analyzing the Options**:
- **Aplysia**: This is a genus of marine mollusks commonly known as sea hares. Aplysia has well-developed parapodia that assist in swimming and movement.
- **Doris**: This is a genus of sea slugs that do not have parapodia. They rely on other forms of locomotion.
- **Chiton**: Chitons have a different body structure and do not possess parapodia. They have a shell made of eight plates and move using a muscular foot.
- **Pila**: This is a genus of freshwater snails that also do not have parapodia. They have a coiled shell and utilize a different method for locomotion.

3. **Identifying the Correct Answer**:
- Among the options, only **Aplysia** possesses parapodia. The other three options (Doris, Chiton, and Pila) do not have these structures.

4. **Conclusion**:
- Therefore, the correct answer to the question "A mollusc with parapodia is" is **Aplysia**.

### Final Answer:
**Aplysia**