Wine and beer are produced directly by fermentation whereas brandy and whisky require both fermentation and distillation. This is because

Options

A. fermentation is inhibited at the alcohol level of `10-18%`
B. distillation prolong storage
C. distillation improves quality
D. distillation purifies the beherage

Answer

To answer the question, "Wine and beer are produced directly by fermentation whereas brandy and whisky require both fermentation and distillation. This is because," we need to analyze the processes involved in the production of these alcoholic beverages.

### Step-by-Step Solution:

1. **Understanding Fermentation**:
- Fermentation is a metabolic process where microorganisms, such as yeast, convert sugars into alcohol and carbon dioxide. This process is responsible for producing beverages like wine and beer.

2. **Alcohol Content in Wine and Beer**:
- The alcoholic content of wine and beer typically ranges from 10% to 15%. This is considered a lower alcohol content compared to spirits.

3. **Limitations of Fermentation**:
- Fermentation has a natural limit to the amount of alcohol it can produce. When the alcohol concentration reaches about 10% to 18%, the fermentation process is inhibited. This means that yeast cells become less active and may die off due to the high alcohol concentration.

4. **Production of Brandy and Whisky**:
- Brandy and whisky, on the other hand, start with fermentation but require an additional step: distillation. Distillation is a process that involves heating the fermented liquid to separate alcohol from water and other components, resulting in a higher concentration of alcohol.

5. **Alcohol Content in Brandy and Whisky**:
- The distillation process allows for the production of beverages with a much higher alcohol content, typically above 20% to 25%. This is why brandy and whisky are classified as hard liquors.

6. **Conclusion**:
- Therefore, the reason brandy and whisky require both fermentation and distillation is that fermentation alone cannot produce the higher alcohol content needed for these beverages. Distillation is necessary to increase the alcohol concentration beyond the limits of fermentation.

### Final Answer:
The correct reason is: **Fermentation is inhibited at the alcohol level of 10-18%.**

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