Alcoholic fermentation is performed by

Options

A. Chlorlla
B. Agaricus
C. Yeast
D. Puccinia

Answer

### Step-by-Step Solution:

1. **Understanding Alcoholic Fermentation**:
- Alcoholic fermentation, also known as ethanol fermentation, is a metabolic process that converts sugars into ethanol and carbon dioxide. This process occurs in the absence of oxygen (anaerobic conditions).

2. **Identifying the Organisms**:
- The question provides four options: cholera, agaricus, yeast, and pacinia. We need to determine which of these organisms is capable of performing alcoholic fermentation.

3. **Analyzing Each Option**:
- **Cholera**: This refers to *Vibrio cholerae*, a bacterium that causes cholera. It does not perform alcoholic fermentation.
- **Agaricus**: This is a genus of mushrooms (e.g., Agaricus bisporus, the common mushroom). While some fungi can ferment, Agaricus is primarily known for its role in decomposing organic matter rather than producing alcohol.
- **Yeast**: Yeasts, particularly *Saccharomyces cerevisiae*, are well-known for their ability to ferment sugars into ethanol and carbon dioxide. This makes yeast the primary organism for alcoholic fermentation.
- **Pacinia**: This is not a commonly recognized organism in the context of fermentation. It may refer to a genus of fungi, but it is not known for alcoholic fermentation.

4. **Conclusion**:
- Based on the analysis, the correct answer is **yeast**, as it is the organism that performs alcoholic fermentation by converting simple sugars into ethanol and carbon dioxide.

### Final Answer:
Alcoholic fermentation is performed by **yeast**.

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