Oxygenated Blood Pathway in Circulation

Steps:

• Oxygenated blood enters the heart via pulmonary veins from the lungs.
• It flows into the left atrium.
• From the left atrium, it passes through the mitral valve to the left ventricle.
• The left ventricle pumps it into the aorta for systemic distribution.

Why D is correct:

• D accurately traces oxygenated blood from pulmonary vein to left atrium, left ventricle, and aorta, following the standard pulmonary-systemic circulation pathway.

Why the others are wrong:

• A: Starts with pulmonary artery, which carries deoxygenated blood to lungs, not oxygenated.
• B: Omits right side structures and has formatting errors; incorrectly implies mixing atria.
• C: Includes right atria and ventricles, which handle deoxygenated blood, not oxygenated.

Final answer: D