Fresh Water Polyp is

Options

A. Hydra
B. Aurelia
C. Physalia
D. Obelia.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the name of the freshwater polyp among the given options: Hydra, Aurelia, Physalia, and Obelia.

2. **Understand the Characteristics of Freshwater Polyps**: Freshwater polyps belong to the phylum Cnidaria. They typically have a cylindrical body that is vase-shaped and can attach to substrates or other polyps.

3. **Analyze the Options**:
- **Hydra**: Known to be a freshwater organism that remains in the polyp form throughout its life.
- **Aurelia**: Commonly known as the moon jelly, it is primarily marine and exists in both polyp and medusa forms.
- **Physalia**: Also known as the Portuguese man o' war, it is a marine organism and not a true polyp.
- **Obelia**: While it has a polyp stage, it is also primarily marine.

4. **Conclusion**: Based on the characteristics and the options provided, Hydra is the only organism that is a freshwater polyp and remains in the polyp form throughout its life.

5. **Final Answer**: Therefore, the correct answer is **Hydra**.

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