Fermentation is a kind of

Options

A. physical process
B. physiological process
C. chemical process
D. all the above

Answer

### Step-by-Step Solution:

1. **Understanding Fermentation**:
- Fermentation is a metabolic process that occurs in the absence of oxygen (anaerobic conditions). It involves the conversion of sugars (like glucose) into other products, such as alcohol or acids, while releasing energy.

2. **Identifying the Nature of the Process**:
- The question asks what kind of process fermentation is. To answer this, we need to categorize fermentation correctly among the options provided.

3. **Evaluating the Options**:
- **Option 1: Physical Process**: This is incorrect because fermentation involves chemical changes in the substances involved.
- **Option 2: Physiological Process**: This is also incorrect, as physiological processes refer to the functions of living organisms and their parts, not specifically to metabolic conversions like fermentation.
- **Option 3: Chemical Process**: This is correct. Fermentation involves chemical reactions where glucose is broken down into ethanol or lactic acid, which is a hallmark of a chemical process.
- **Option 4: All of the above**: This is incorrect since not all the previous options are correct.

4. **Conclusion**:
- Based on the evaluation of the options, the correct answer is that fermentation is a **chemical process**.

### Final Answer:
Fermentation is a kind of **chemical process**.

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