Which of the following characteristic is not of phylum mollusca :-

Options

A. Soft body covered usually by a shell
B. Segmented body
C. Triploblastic
D. Presence of coelom

Answer

To determine which characteristic is not associated with the phylum Mollusca, we will analyze each option provided.

### Step-by-Step Solution:

1. **Identify the Characteristics of Phylum Mollusca**:
- Mollusks are known for having soft bodies, which are often covered by a shell made of calcium carbonate. They are also characterized by their body structure, which includes a mantle, a foot, and visceral mass.

2. **Evaluate Option A: Soft body covered usually by a shell**:
- This is a defining characteristic of mollusks. Therefore, this option is **not the correct answer**.

3. **Evaluate Option B: Segmented body**:
- Mollusks do not have a segmented body. This characteristic is typically associated with phylum Annelida (segmented worms). Thus, this option is indeed **not a characteristic of phylum Mollusca**.

4. **Evaluate Option C: Triploblastic**:
- Mollusks are triploblastic, meaning their bodies are derived from three germ layers: ectoderm, mesoderm, and endoderm. Therefore, this option is **not the correct answer**.

5. **Evaluate Option D: Presence of coelom**:
- Mollusks do possess a coelom, although it is reduced compared to other animal phyla. Thus, this option is also **not the correct answer**.

### Conclusion:
The characteristic that is **not** associated with phylum Mollusca is **Option B: Segmented body**.

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