Metameric segmentation is the characteristic of

Options

A. Mollusca and chordata
B. Platyhelminthes and Arthropoda
C. Echinodermata and Annelida
D. Annelida and Arthropoda .

Answer

**Step-by-Step Solution:**

1. **Understanding Metameric Segmentation**:
- Metameric segmentation refers to the division of the body into repeated segments or metameres. This type of segmentation is also known as true segmentation.

2. **Identifying Phyla with Metameric Segmentation**:
- Metameric segmentation is a characteristic feature of certain animal phyla. The most notable phyla that exhibit this feature are Annelida (segmented worms) and Arthropoda (insects, arachnids, crustaceans).

3. **Analyzing the Options**:
- Option a: Mollusca and Chordata - Neither of these phyla exhibit metameric segmentation.
- Option b: Platyhelminth and Arthropoda - Platyhelminthes (flatworms) do not show metameric segmentation.
- Option c: Echinodermata and Annelidia - Echinoderms (like starfish) do not exhibit metameric segmentation.
- Option d: Annelida and Arthropoda - Both of these phyla exhibit metameric segmentation.

4. **Conclusion**:
- Based on the analysis, the correct answer is option d: Annelida and Arthropoda.

**Final Answer**: Metameric segmentation is the characteristic of **Annelida and Arthropoda**.

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