A. renal vein
B. hepatic portal vein
C. pulmonary artery
D. pulmonary vein
Correct Answer:
Option C – pulmonary artery
Explanation
Option C is correct. This is because for deoxygenated blood (blood containing carbon (iv) oxide) in the heart to be returned back to the lungs for the removal of the CO2, pulmonary artery aids in the process.