Which of the following is the least action children and adolescents can take to combat obesity? a. adding berries or bananas to cereal or toast b. drinking more fruit juices to replace water c. doing jumping jacks during commercial breaks d. trading healthy recipes with friends

C. doing jumping jacks is the least helpful. Because either way the child is still siting down after that 3 minute break. Human bodies need more than that to fight obesity.
And the other options given are bigger helping hands, because they concern eating healthy foods.

It would be the oxygen reaction with whatever is inside the ballon.