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Option 1: Veins - This is the correct answer. Veins are blood vessels that carry deoxygenated blood from different parts of the body back to the heart. Unlike arteries, which carry oxygenated blood away from the heart, veins have valves that help prevent the backflow of blood. The deoxygenated blood in the veins is then sent to the lungs to be oxygenated before returning to the heart.
Option 2: Arteries - This is incorrect. Arteries carry oxygenated blood away from the heart to various parts of the body. They do not bring deoxygenated blood back to the heart.
Option 3: Nerves - This is incorrect. Nerves are not involved in the transport of blood in the circulatory system.
Option 4: Lungs - This is incorrect. While the lungs play a role in oxygenating blood, they do not bring deoxygenated blood from different parts of the body to the heart. That task is performed by the veins.