The answer would be B:The data suggests that exercise increases the rate of cellular respiration because more carbon dioxide was produced.
The data has a consistently show that the time needed to change BTB color in after exercise group is much shorter(less than half) compared to before exercise group. If the time needed longer, this show that the amount carbon dioxide removed from the lungs is much higher. The reaction that provide energy for the muscle will produce carbon dioxide as side product in cellular respiration.
