Hydra is

Options

A. Coral
B. Worm
C. Polyp
D. Medusa

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about Hydra. It is essential to recognize that Hydra is a type of organism that belongs to a specific biological classification.

2. **Classification**: Hydra is classified under the phylum **Cnidaria**. This phylum includes various aquatic organisms known for their stinging cells (cnidocytes).

3. **Habitat**: Hydra is a **freshwater organism**, meaning it is typically found in freshwater environments such as ponds, streams, and lakes.

4. **Body Structure**: Hydra has a simple body structure characterized by a tubular shape with **tentacles**. These tentacles are equipped with stinging cells that help in capturing prey.

5. **Reproductive Forms**: Hydra exhibits two forms:
- **Polyp**: This is the asexual reproductive form of Hydra. It is usually attached to a substrate and can reproduce by budding.
- **Medusa**: This is the sexual reproductive form, which is free-swimming and typically releases gametes for reproduction.

6. **Regeneration**: Hydra is known for its remarkable ability to regenerate lost body parts, which is a significant aspect of its biology.

7. **Conclusion**: Based on the above points, we can conclude that Hydra is best described as a **polyp**, which is a type of cnidarian, and it is a freshwater organism.

**Final Answer**: Hydra is a freshwater organism belonging to the phylum Cnidaria, characterized by its polyp form and regeneration abilities.

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