Answer:
The correct option is C) The amount of glucose decreases.
Explanation:
During exercise, our body starts utilizing sugar which is stored in the liver and muscles. To rebuild these stores of sugar, sugar is drawn from the circulating blood. Hence, the amount of sugar will decrease during intense, prolonged exercises.
Other options like option A are false because the amount of ATP will also start to decline during exercise as more ATP would be utilized by the muscle cells to carry out the workout.