Step 1: Understanding Chemical Compounds
- The given structure corresponds to sodium benzoate, which is a well-known food preservative.
Step 2: Checking Other Options
- The first structure is not an antibiotic; antibiotics are typically complex organic molecules.
- Propanoic acid salts (such as sodium propionate) are used as food preservatives, not antioxidants.
- Veronal is a barbiturate sedative, not an analgesic.
Thus, the correct answer is the food preservative.
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