The colour of blood in earthworm is

Options

A. Blue
B. Red
C. Brown
D. Colourless

Explanation

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the color of blood in the earthworm, which belongs to the phylum Annelida.

2. **Understand the Circulatory System**: Earthworms have a closed circulatory system. This means that their blood circulates within specialized vessels, including blood vessels and capillaries.

3. **Identify the Blood Pigment**: The blood pigment responsible for transporting oxygen in earthworms is hemoglobin. Hemoglobin is an iron-containing protein that gives blood its color.

4. **Determine the Color of Blood**: In earthworms, hemoglobin is present in the blood, and it is dissolved in the plasma rather than being contained within red blood cells (RBCs) as in humans. The presence of hemoglobin in the blood gives it a red color.

5. **Conclusion**: Based on the presence of hemoglobin, we conclude that the color of blood in earthworms is red.

6. **Select the Correct Option**: Among the options provided (blue, red, brown), the correct answer is red.

**Final Answer**: The color of blood in earthworm is red.

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