The correct answer is (d), sodium benzoate. Sodium benzoate is a food preservative that is used to prevent the growth of bacteria and fungi in food. It is a white, crystalline powder that is soluble in water. Sodium benzoate is often used in combination with other preservatives, such as potassium sorbate, to provide a more effective barrier against spoilage.
Sodium hydroxide (a) is a strong base that is used in a variety of industrial processes, including the production of soap, paper, and textiles. It is also used in some household products, such as drain cleaners and oven cleaners. Sodium hydroxide is not a food preservative.
Sodium sulfate (b) is a salt that is used in a variety of industrial processes, including the production of paper, glass, and detergents. It is also used in some household products, such as laundry detergent and dishwashing detergent. Sodium sulfate is not a food preservative.
Phenol (c) is a chemical that is used in a variety of industrial processes, including the production of plastics, resins, and dyes. It is also used in some household products, such as disinfectants and antiseptics. Phenol is not a food preservative.