Which two body systems work together to deliver oxygen to cells? A. the digestive and respiratory systems B. the respiratory and circulatory systems C. the digestive and circulatory systems D. the circulatory and excretory systems

The correct answer is option B, that is, the respiratory and circulatory systems.

The respiratory and circulatory system functions together to circulate oxygen and blood all through the body. The movement of air takes place in and out of the lungs via the bronchi, trachea, and bronchioles. The movement of blood takes place in and out of the lungs via the pulmonary veins and arteries, which associate with the heart.

The pulmonary arteries mediate deoxygenated blood to the lungs from the heart, and the pulmonary veins carry oxygenated blood to the heart again so that it can be distributed to the rest of the body.