Demarco lifts weights in his home gym every morning before preparing for work. He knows that he needs to do other types of exercise, but his schedule is packed. Since his time is limited, what would be one way that Demarco could add more endurance exercise to his daily routine?

A.
Use ankle or wrist weights during his regular workout session.

B.
Trade out his desk chair for a special balance ball.

C.
Take the stairs up to his office instead of the elevator.

D.
Do five minutes of stretching for every hour he works.