Correct Answer: lemon

Solution : The correct option is lemon .

Lemon contains citric acid in its free form. Lemons' sour flavour is caused by a natural organic acid. Lemon juice contains 5% to 6% citric acid. Other citrus fruits, such as oranges, limes, and grapefruits, contain citric acid. Other fruits and vegetables that contain it include tomatoes, pineapples, and kiwis. Citric acid has several applications. It is used in food, and drinks as a flavouring ingredient, as a preservative, and as a cleaning agent. It is also used to make medications and cosmetics.