In which of the following is citric acid present?

Lemon

The correct answer is option2. Lemon.

Citric acid is present in Lemon.

Citric acid is commonly found in citrus fruits such as lemons, oranges, limes, and grapefruits. Lemons are particularly rich in citric acid, which contributes to their tart flavor. Citric acid is also often used as a flavoring agent and preservative in various food and beverage products due to its sour taste and antioxidant properties.

While other options such as tamarind, black gram, and curd are all food items, they do not naturally contain significant amounts of citric acid like citrus fruits do.