What is the pathway of blood flow through the heart starting from the right atrium?

The correct answer outlines the detailed pathway of blood flow through the heart, starting from the right atrium. Blood from the systemic circulation first enters the right atrium. From there, it flows through the tricuspid valve into the right ventricle.

Upon contraction of the right ventricle, blood is ejected through the pulmonic valve into the pulmonary artery, which carries it to the lungs. In the lungs, carbon dioxide is exchanged for oxygen during respiration. The oxygenated blood then returns to the heart via the pulmonary veins, entering the left atrium.

The blood then moves through the bicuspid (mitral) valve into the left ventricle. Finally, when the left ventricle contracts, blood is pushed through the aortic valve into the aorta, which distributes it to the rest of the body.

This option accurately follows the sequence of blood flow through the heart and specifies the relevant structures involved in this circulatory process, ensuring a clear understanding of how deoxygenated and oxygenated blood is handled by the heart.