Acetic acid is manufactured by the fermentation of `:`

Options

A. Ethanol
B. Methanol
C. Ethanal
D. Methanal

Answer

### Step-by-Step Solution:

1. **Understanding Acetic Acid**: Acetic acid is a simple carboxylic acid with the formula CH₃COOH. It is commonly known as vinegar when diluted.

2. **Identifying the Source**: Acetic acid can be produced through the fermentation process, which involves the conversion of organic compounds by microorganisms.

3. **Role of Bacteria**: The specific bacteria involved in the fermentation process to produce acetic acid is called Acetobacter. This aerobic bacterium oxidizes alcohols into acetic acid.

4. **Determining the Starting Material**: Since acetic acid has two carbon atoms, the starting material must also have two carbon atoms. This is because oxidation does not change the number of carbon atoms in the molecule.

5. **Identifying the Alcohol**: The only two-carbon alcohol that can be oxidized to acetic acid is ethanol (C₂H₅OH or CH₃CH₂OH).

6. **Fermentation Process**: In the fermentation process, ethanol is mixed with Acetobacter, which supplies oxygen and facilitates the oxidation of ethanol to acetic acid.

7. **Conclusion**: Therefore, the correct answer to the question "Acetic acid is manufactured by the fermentation of:" is ethanol.

### Final Answer:
Acetic acid is manufactured by the fermentation of **ethanol**.

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