Number of eyes present on the prostomium of Nereis is

Options

A. (a) four
B. (b) three
C. (c) two
D. (d) one

Answer

To determine the number of eyes present on the prostomium of Nereis, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Nereis**: Nereis is a genus of marine polychaete worms that belong to the phylum Annelida. Understanding the classification helps in recognizing its anatomical features.

2. **Understand the Structure of Nereis**: The prostomium is the first segment of the body located just in front of the mouth. It is important to know where the prostomium is located to identify its features.

3. **Locate the Eyes**: On the prostomium of Nereis, there are structures that represent the eyes. In the video, these are highlighted and described as being present on the prostomium.

4. **Count the Eyes**: The transcript mentions that Nereis has two sets of eyes. Each set contains two eyes, leading to a total of four eyes.

5. **Conclusion**: Therefore, the number of eyes present on the prostomium of Nereis is 4.

### Final Answer:
The number of eyes present on the prostomium of Nereis is **4**.

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