Vinegar prevents spoilage of:

Options

A. jams
B. jellies
C. pickles
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about what type of food vinegar helps to prevent spoilage.

2. **Identifying the Options**: The options given are:
- 1st option: Jam
- 2nd option: Jellies
- 3rd option: Pickles
- 4th option: None of these

3. **Analyzing the Role of Vinegar**: Vinegar is an acidic substance that creates an environment where bacteria and microorganisms cannot thrive. This makes it an effective preservative.

4. **Evaluating Each Option**:
- **Jam**: Typically preserved with sugar, not vinegar.
- **Jellies**: Also preserved with sugar, not vinegar.
- **Pickles**: Often preserved using vinegar (as well as salt and sometimes oil) to prevent spoilage.

5. **Conclusion**: Based on the analysis, vinegar is primarily used to prevent the spoilage of pickles.

6. **Final Answer**: The correct answer is **3rd option: Pickles**.

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