Which molluscan group is primarily used in pearl production ?

Options

A. Pelecypods
B. Gastropods
C. Cephalopods
D. Monoplacophorans.

Answer

To answer the question "Which molluscan group is primarily used in pearl production?", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Molluscan Groups**: The question provides four options: Pellicipods, Gastropods, Cephalopods, and Monoplacophorans. We need to analyze each group to determine which one is primarily associated with pearl production.

2. **Understand the Characteristics of Pellicipods**: Pellicipods, also known as bivalves, are characterized by having two shells (valves). They include organisms such as oysters, clams, and scallops.

3. **Link Pellicipods to Pearl Production**: Among the bivalves, oysters are particularly known for their ability to produce pearls. Pearls are formed as a response to irritants entering the oyster's shell, where the oyster secretes layers of nacre around the irritant, eventually forming a pearl.

4. **Consider Other Groups**:
- **Gastropods**: This group includes snails and slugs, which do not produce pearls.
- **Cephalopods**: This group includes squids and octopuses, which are not known for pearl production.
- **Monoplacophorans**: This is a lesser-known group that does not contribute to pearl production.

5. **Conclusion**: Based on the characteristics and the known associations of these groups, Pellicipods are the primary molluscan group used in pearl production.

### Final Answer:
The correct option is **Pellicipods**.

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