Acetobacter aceti converts ............... into vinegar.

Explanation

**Step-by-Step Solution:**

1. **Identify the Microbe**: The question asks about Acetobacter aceti, which is a type of bacteria known for its role in the fermentation process.

2. **Understand the Process**: Acetobacter aceti is involved in the conversion of certain substances into vinegar. Specifically, it is known for oxidizing ethanol.

3. **Recognize the Substrate**: Ethanol, also known as ethyl alcohol, is the primary substrate that Acetobacter aceti acts upon.

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