Blood pigment of annelids is

Options

A. haemoglobin
B. cyanin
C. haematin
D. haemocyanin

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the blood pigment found in annelids.

2. **Understand the Options**: The options provided are hemoglobin, cyanin, hematin, and hemocyanin.

3. **Analyze Each Option**:
- **Hemoglobin**: This is a well-known red pigment responsible for carrying oxygen in many organisms, including humans and some annelids.
- **Cyanin**: This pigment is typically found in plants and is not related to blood pigments in animals.
- **Hematin**: This is a product of the oxidation of heme and is not primarily involved in oxygen transport.
- **Hemocyanin**: This is a blue pigment found in some invertebrates, such as mollusks and arthropods, and contains copper instead of iron.

4. **Focus on Annelids**: In annelids, the primary blood pigment is hemoglobin. While there may be other pigments present, hemoglobin is the main one responsible for oxygen transport.

5. **Conclusion**: Based on the analysis, the correct answer to the question is hemoglobin.

**Final Answer**: The blood pigment of annelids is **hemoglobin**.

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