Final answer:
The right atrium and right ventricle of the right heart pump deoxygenated blood through the pulmonary circulation to the lungs for oxygenation.
Step-by-step explanation:
The right atrium and the right ventricle are part of the right heart and are primarily involved in pumping deoxygenated blood through the pulmonary circulation. Deoxygenated blood flows into the right atrium from the body via the superior vena cava and the inferior vena cava. After moving through the right atrium, the blood passes through the tricuspid valve into the right ventricle, which then pumps it through the pulmonary valve into the pulmonary artery. The pulmonary artery carries the blood to the lungs where it becomes oxygenated. Hence, the correct option that describes where the right heart pumps blood through is 'B. the pulmonary circulation'.