Pick the odd one out.

Options

A. Amoeba
B. Yeast
C. Hydra
D. Fungi

Answer

### Step-by-Step Solution:

1. **Identify the Options**: The options given are Amoeba, Yeast, Hydra, and Fungi.

2. **Classify Each Option**:
- **Amoeba**: This is a single-celled organism that belongs to the kingdom Protista. It is microscopic and cannot be seen with the naked eye.
- **Yeast**: This is also a microorganism, specifically a type of fungus, and falls under the kingdom Fungi. It is also microscopic.
- **Hydra**: This is a multicellular organism that is visible to the naked eye. It belongs to the phylum Cnidaria and is classified as an animal.
- **Fungi**: This refers to a group of microorganisms that includes yeasts and molds, and it falls under the kingdom Fungi.

3. **Compare the Characteristics**:
- **Amoeba** and **Yeast** are both microorganisms and cannot be seen without a microscope.
- **Fungi** (as a category) includes microorganisms like Yeast.
- **Hydra**, on the other hand, is a multicellular organism that can be seen without a microscope.

4. **Determine the Odd One Out**: Since Amoeba, Yeast, and Fungi are all microorganisms, while Hydra is a multicellular organism, Hydra is the odd one out.

5. **Conclusion**: The odd one out is **Hydra** (Option C).