Which of the following is commonly called "pearl oyster" ?

Options

A. Limulus
B. Dentalium
C. Pinctada
D. Aurelia

Explanation

To answer the question "Which of the following is commonly called 'pearl oyster'?", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Organisms**: We need to look at the list of organisms provided in the question. In this case, we have four options: Lumulus, Dentalium, Pentada, and Aurelia.

2. **Research Common Names**: For each organism, we need to find out their common names:
- **Lumulus**: The common name is King Crab.
- **Dentalium**: The common name is Tuskshell.
- **Pentada**: The common name is Pearl Oyster.
- **Aurelia**: The common name is Jellyfish.

3. **Match the Common Name**: Now, we need to match the common name "pearl oyster" with the organism:
- From our research, we find that Pentada is commonly known as Pearl Oyster.

4. **Conclusion**: Therefore, the organism that is commonly called "pearl oyster" is **Pentada**.

### Final Answer:
The organism commonly called "pearl oyster" is **Pentada**.

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