Which of the following preservatives is used for the preparation of tomato ketchup?

✅ Explanation: Sodium benzoate is a common preservative used in acidic foods like tomato ketchup. It works by inhibiting the growth of microorganisms like bacteria and fungi, thereby extending the shelf life of the product. It's particularly effective in acidic environments.

🛑Other Options Explanations:
-Option A: Potassium metabisulphite: This is primarily used as an antioxidant and preservative in foods like dried fruits and wine. It can also be used to sanitize food processing equipment.
-Option D: Citric acid: While citric acid is naturally present in tomatoes and contributes to the ketchup's flavor and acidity. It can act as an additional preservative, but its main function is to adjust the pH.