In alcohol fermentation

Options

A. carbon dioxide is taken in
B. oxygen is taken in
C. oxygen is given out
D. carbon dioxide is given out

Answer

### Step-by-Step Solution:

1. **Understanding Alcohol Fermentation**: Alcohol fermentation, also known as ethanol fermentation, is a biological process where sugars are converted into alcohol (ethanol) and carbon dioxide. This process occurs in the absence of oxygen, making it anaerobic.

2. **Identifying the Inputs and Outputs**: In this process, sugars (like glucose) are the primary input. The outputs of alcohol fermentation include ethanol, carbon dioxide (CO2), water, and heat.

3. **Analyzing the Options**: The question provides four options regarding the involvement of oxygen and carbon dioxide:
- Carbon dioxide is taken in
- Oxygen is taken in
- Oxygen is given out
- Carbon dioxide is given out

4. **Eliminating Incorrect Options**: Since alcohol fermentation is an anaerobic process, oxygen is not required. Therefore, the options stating that oxygen is taken in or given out can be eliminated.

5. **Identifying the Correct Answer**: The only relevant output of alcohol fermentation is carbon dioxide. Since carbon dioxide is produced as a by-product of the fermentation process, the correct answer is that carbon dioxide is given out.

### Final Answer:
In alcohol fermentation, carbon dioxide is given out.

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