Segmentation in the body is first observed in which of the following:

Options

A. Platyhelminthes
B. Aschelminthes
C. Annelida
D. Arthropoda

Explanation

To solve the question regarding where segmentation in the body is first observed, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Segmentation**: Segmentation, also known as metamerism, refers to the division of the body into repetitive segments. This characteristic is significant in the classification of various animal phyla.

**Hint**: Recall that segmentation is a key feature that helps in identifying certain groups of animals.

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