Which of the following explains the movement of oxygen during gas exchange between the alveoli and the capillaries?

A. Oxygen moves from the alveoli, then to the capillaries, and back to the alveoli.

B. Oxygen moves from the alveoli to the blood in the capillaries.

C. Oxygen moves from the capillaries, then to the alveoli, and back to the capillaries.

D. Oxygen moves from the blood in the capillaries to the alveoli.​