Final answer:
The correct statement about human blood vessels is 'd. Pulmonary veins carry oxygen-rich blood to the heart', as pulmonary veins are the exception to the general rule and carry oxygenated blood from the lungs to the heart.
Step-by-step explanation:
The correct statement about human blood vessels is: d. Pulmonary veins carry oxygen-rich blood to the heart. In the pulmonary circuit, the pulmonary veins transport freshly oxygenated blood from the lungs back to the heart. In contrast, the pulmonary artery carries oxygen-poor blood from the heart to the lungs. It's important to note that arteries usually carry oxygenated blood away from the heart and veins carry deoxygenated blood towards the heart, but the pulmonary vessels are an exception to this rule. Hence, options a, b, c, and e are incorrect because they either misunderstand the direction of blood flow or mix up oxygenated and deoxygenated states.