The correct answer is option 1 - Fructose. Ripe grapes are known to contain fructose, a type of sugar commonly found in sweet fruits. Fructose is a monosaccharide, meaning it is a simple sugar that cannot be broken down into smaller carbohydrate molecules. It is naturally occurring in many fruits, including grapes, and it is responsible for their sweet taste. Fructose is easily absorbed by the body and can be used as a source of energy. It is also commonly used as a sweetener in processed foods and beverages. Therefore, the presence of fructose is one of the reasons why ripe grapes are known for their natural sweetness.