The blood circulates in only one direction. Arterial blood is oxygenated through the lungs and distributed through the heart to the body; venous blood, rich in carbon dioxide (low in oxygen), returns to the heart through the superior vena cava and inferior vena cava and reaches the right atrium, so the statement shown in the question is true. The atrial space is filled with venous blood from where it is then sent to the right ventricle. The right ventricle pushes the blood to the lungs like a pump to be oxygenated.
The pulmonary veins then carry the oxygenated blood back to the left side of the heart, where it first reaches the left atrium and then goes to the left ventricle, from where it is pumped into the aorta.
The answer is true because t<span>he right ventricle pumps blood to the heart to become saturated with oxygen, this is then returned to the left atria and pumped out of the left ventricle to the rest of the body </span>
