Acetic acid is produced by a

Options

A. fungus
B. bacterium
C. Yeast
D. virus

Answer

To answer the question "Acetic acid is produced by a," we can follow these steps:

### Step 1: Identify the Microorganisms
Acetic acid is primarily produced by certain types of bacteria. The most notable among these are:

- **Acetobacter**: This genus of bacteria is well-known for its ability to convert ethanol (alcohol) into acetic acid through the process of fermentation.
- **Acetobutylicum**: While this bacterium is primarily known for producing butyric acid and acetone, it can also produce acetic acid under certain conditions.

### Step 2: Understand the Process
The production of acetic acid occurs through fermentation. In this process, the bacteria oxidize ethanol in the presence of oxygen, leading to the formation of acetic acid. This is an important step in various fermentation processes, especially in the production of vinegar.

### Step 3: Conclusion
Therefore, the primary answer to the question is that acetic acid is produced by **Acetobacter**.

### Final Answer:
Acetic acid is produced by **Acetobacter**.

---