Metameric segmentation is main feature of Annelids/Arthropoda.

Explanation

**Step-by-Step Solution:**

1. **Understanding Metameric Segmentation**:
- Metameric segmentation refers to the division of the body into repeated segments or metameres. Each segment is structurally and functionally similar but can also have specialized functions.

2. **Identifying the Organisms**:
- This type of segmentation is primarily observed in the phylum Annelida, which includes organisms like earthworms, polychaetes, and leeches.

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