Final answer:
The pulmonary vein does not return blood to the right atrium; it returns oxygenated blood from the lungs to the left atrium. The superior and inferior venae cavae and the coronary sinus are the vessels that return deoxygenated blood to the right atrium.
Step-by-step explanation:
The option that does NOT return blood to the right atrium of the heart is B. pulmonary vein. The two major systemic veins, the superior and inferior venae cavae, and the large coronary vein called the coronary sinus, drain into the right atrium. The superior vena cava brings deoxygenated blood from the upper part of the body, while the inferior vena cava brings deoxygenated blood from the lower part.
The coronary sinus drains blood from the heart muscle. In contrast, blood in the pulmonary vein is oxygenated because it comes from the lungs, where gas exchange occurs, and thus it returns blood to the left atrium, not the right.