Final answer:
Deoxygenated blood flows from the right ventricle through the pulmonary arteries to the lungs, where it becomes oxygenated and returns to the heart to be pumped through the aorta. Therefore, the correct option is B.
Step-by-step explanation:
The flow of blood from the right side of the heart back to the same site involves deoxygenated blood being pumped from the right ventricle to the pulmonary arteries, which then leads to the lungs for gas exchange. The now oxygen-rich blood returns to the left atrium via pulmonary veins, enters the left ventricle, and is pumped through the aorta to the rest of the body.
The blood passes through smaller arteries and capillaries, where oxygen and nutrients are delivered to tissues. Nutrient-rich blood from the small intestine is collected into the hepatic portal system, which carries it to the liver for processing before being returned to circulation and eventually back to the right atrium of the heart via the venous system.
During digestion, the veins that collect blood from the small intestine empty into the hepatic portal system, ensuring the nutrients absorbed are routed through the liver. Proteins and carbohydrates are transported directly by the blood vessels while lipids are absorbed differently, via structures in the lymphatic system called lacteals. Thus, the correct answer to the given choices is b) Deoxygenated blood; via arteries; carbohydrates.