Neopilina is a connecting link between

Options

A. Arthropoda and Mollusca
B. Annelida and mollusca
C. Mollusca and Echinodermata
D. Mollusca and Helminthes

Answer

### Step-by-Step Solution:

1. **Understanding Neopilina**: Neopilina is a unique organism classified as a mollusk. It is significant because it exhibits characteristics that are not typical of other mollusks.

2. **Identifying Features**: Neopilina is known as the only segmented mollusk. This means it has a body structure that is divided into segments, which is a characteristic feature of annelids (segmented worms).

3. **Comparing with Annelids**: Annelids are a group of invertebrates that are characterized by their segmented bodies. Neopilina shares this segmentation, which makes it an interesting subject of study in evolutionary biology.

4. **Structural Characteristics**: Neopilina has a cup-shaped shell similar to that of limpets and possesses a visceral mass that is divided into five segments. Each segment contains a pair of structures such as shells, muscles, gills, auricles, and nephridia.

5. **Conclusion**: Given that Neopilina exhibits features of both mollusks and annelids, it serves as a connecting link between these two groups. Therefore, the correct answer to the question is that Neopilina is a connecting link between annelids and mollusks.

### Final Answer:
Neopilina is a connecting link between **Annelids and Mollusca**.

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