Where is maltose primarily found?

Maltose is primarily found in grains, making this choice the correct answer. Maltose is a disaccharide composed of two glucose units and is formed during the breakdown of starch. Grains, such as barley, contain amylase enzymes that break down starch into maltose during the germination process. This is particularly important in the production of malted foods and beverages, such as beer and malted milk.

The other options do not primarily contain maltose. Fruits typically contain higher levels of fructose and glucose as their main sugars, while dairy products primarily contain lactose. Vegetables, on the other hand, may have a variety of carbohydrates, but they are not significant sources of maltose specifically. Therefore, grains are the best answer for the primary source of maltose.