Setae help in locomotion in earthworm but are not uniformly present in all the segments. They are present in

Options

A. 1st segment
B. last segment
C. clitellar segment
D. 20th -22 nd segment

Explanation

### Step-by-Step Solution:

1. **Understanding the Structure of Earthworm**:
- The body of an earthworm is segmented, which means it is divided into multiple segments both externally and internally.

2. **Identifying the Function of Setae**:
- Setae are small bristle-like structures found on the body of the earthworm. Their primary function is to aid in locomotion.

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