Mushroom is

Options

A. Mucor
B. Agaricus
C. Yeast
D. Panicillium

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks to identify what a mushroom is from the given options.

2. **Identifying the Options**:
- Option 1: Mucor
- Option 2: Agaricus
- Option 3: Yeast
- Option 4: Penicillium

3. **Analyzing Each Option**:
- **Option 1: Mucor**: Mucor is a genus of fungi but is not classified as a mushroom. It is typically found in soil and decaying organic matter.
- **Option 2: Agaricus**: Agaricus is a genus of fungi that includes mushrooms, specifically the common edible mushroom known as Agaricus bisporus. This is the correct option.
- **Option 3: Yeast**: Yeast is a type of fungus but is unicellular and does not form mushrooms. It reproduces by budding.
- **Option 4: Penicillium**: Penicillium is another genus of fungi known for its role in antibiotic production (like penicillin) but is not a mushroom.

4. **Conclusion**: Based on the analysis, the correct answer is **Option 2: Agaricus**, as it is the genus that includes mushrooms.

### Final Answer:
Mushroom is **Agaricus**.

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