Blood vascular system of earthworm is of

Options

A. open type
B. closed type
C. portal type
D. none of the these.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the blood vascular system of the earthworm. The scientific classification of the earthworm places it in the phylum Annelida.

2. **Understanding Blood Vascular Systems**: There are two main types of blood vascular systems in animals: open and closed.
- In an **open circulatory system**, blood flows freely in the body cavity and is not always contained within blood vessels.
- In a **closed circulatory system**, blood is confined to vessels (arteries, veins, and capillaries) and does not fill the body cavity.

3. **Classify the Earthworm's Circulatory System**: Earthworms possess a closed circulatory system. This means that their blood circulates through a network of vessels.

4. **Components of the Earthworm's Circulatory System**: The earthworm has:
- A dorsal blood vessel (which acts like a heart).
- A ventral blood vessel.
- Capillaries that connect arteries and veins, allowing for the exchange of nutrients and gases.

5. **Conclusion**: Based on the classification and characteristics of the earthworm's circulatory system, the correct answer to the question is that the blood vascular system of the earthworm is of the **closed type**.

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