Which main coronary artery bifurcates into two smaller arteries?

The left coronary artery is the correct answer because it bifurcates into two major branches: the left anterior descending artery (LAD) and the left circumflex artery (LCx). This bifurcation is vital for supplying the left side of the heart with oxygenated blood.

The right coronary artery, while significant in supplying the heart, does not bifurcate in the same manner as the left coronary artery; it primarily supplies the right atrium and parts of the right ventricle, as well as the inferior aspect of the heart.

The pulmonary artery carries deoxygenated blood from the right ventricle to the lungs and does not form smaller arteries specifically for the heart’s coronary circulation. Similarly, the aorta is the major artery that distributes oxygenated blood from the heart to the rest of the body, but it does not bifurcate into smaller arteries that specifically serve the coronary supply.

Thus, the left coronary artery is distinct in its bifurcation into two main branches, making it the correct choice in this context.