Why is the main carbohydrate in milk not classified as a monosaccharide?

Lactose is the main carbohydrate in milk, and it is not classified as a monosaccharide because it is a disaccharide. A monosaccharide is the simplest type of carbohydrate and cannot be broken down into smaller carbohydrates. Lactose is made up of two monosaccharides, glucose, and galactose, linked together. Therefore, it is a disaccharide and not a monosaccharide.