Final answer:
Dietary fiber is composed of long chains of monosaccharides connected by glycosidic bonds that cannot be degraded by human digestive enzymes, unlike starch which humans can digest. The specific type of fiber that matches this description is cellulose.
Step-by-step explanation:
The substance referred to in the question is dietary fiber. Dietary fiber is a complex carbohydrate composed of long chains of monosaccharides connected by glycosidic bonds. Unlike other carbohydrates, human digestive enzymes cannot break down these bonds, leading to its classification as a non-digestible component.
A significant type of dietary fiber that resists degradation by human digestive enzymes is cellulose, a structural component found in the cell walls of plants. Cellulose consists of long chains of glucose molecules connected by β-glycosidic bonds. The specific arrangement of these bonds, differing from those in digestible carbohydrates like starch, renders cellulose resistant to enzymatic hydrolysis in the human digestive system.
The inability to digest cellulose has physiological benefits, as it contributes to the bulk and texture of plant-based foods, aids in bowel regularity, and offers potential health advantages. Therefore, the accurate answer to the question is indeed a. fiber.