Deoxygenated blood flows from body tissues to lungs or heart

Steps:

• Deoxygenated blood returns from body to right side of heart via systemic veins like vena cava and hepatic vein.
• Pulmonary arteries carry deoxygenated blood from right ventricle to lungs for oxygenation.
• Pulmonary veins carry oxygenated blood from lungs to left atrium, unlike other veins.
• Eliminate options with any oxygenated vessels like aorta or pulmonary veins.

Why B is correct:

• Pulmonary artery transports deoxygenated blood from heart to lungs; hepatic vein returns deoxygenated blood from liver to inferior vena cava, per systemic circulation definitions.

Why the others are wrong:

• A: Aorta carries oxygenated blood from left ventricle to body.
• C: Pulmonary vein carries oxygenated blood from lungs to heart.
• D: Pulmonary vein carries oxygenated blood from lungs to heart.

Final answer: B