The graph below shows the change in blood glucose level during prolonged exercise. Which of the following statements explains the change in blood glucose level shown in the graph? Change in Blood Glucose Level 6.0 5.5+ 5.0+ Blood Glucose Concentration (mm) 45+ 40+ 3.5+ 3.0 + 0 30 20 Exercise Time (min) 60 O Glucose diffused from muscle cells into the bloodstream. hy Glucose was broken down to produce ATP for energy. Proteins combined with glucose to produce ADP for energy. Polysaccharides were made from glucose in metabolic pathways.​