Final answer:
In pulmonary circulation, the pulmonary veins carry oxygenated blood to the left atrium of the heart.
Step-by-step explanation:
In pulmonary circulation, the veins that carry highly oxygenated blood are known as the pulmonary veins. These veins return oxygen-rich blood from the lungs to the heart, specifically into the left atrium. The left atrium then pumps the blood into the left ventricle. From there, the left ventricle pumps the oxygenated blood into the aorta and onwards to the many branches of the systemic circuit where it will supply oxygen to the body's tissues and organs.