Which of the following carbohydrates is commonly broken down to provide energy for the body?

Starch is a polysaccharide that serves as a primary storage form of energy in plants. It is composed of long chains of glucose units, which is a simple sugar that the body can readily use for energy. When consumed, enzymes in the digestive system, particularly amylase, break down starch into its glucose monomers, which can then be absorbed into the bloodstream. Once in the bloodstream, glucose is a crucial source of energy for cells throughout the body, especially for the brain and muscles during physical activity.

Cellulose, while also a carbohydrate, is a structural component of plant cell walls and cannot be digested by humans due to the lack of the necessary enzymes to break down its beta-glycosidic bonds. Sucrose, the common table sugar, does provide energy but is more quickly broken down into glucose and fructose; however, it is not as primary a source as starch. Fructose is a simple sugar that is also used for energy, but it primarily comes from fruits and is not as significant as starch in terms of providing a sustained energy source in the diet. Thus, starch is the most relevant carbohydrate that is efficiently broken down to provide energy for the body.