Final answer:
The renal artery conducts oxygenated blood into the kidney from the abdominal aorta, eventually branching into smaller vessels to supply blood to the nephrons for filtration.
Step-by-step explanation:
The correct answer is d. Renal artery.
The renal artery is the blood vessel that originates from the abdominal aorta and enters the kidney, supplying it with oxygen-rich blood. After entering the kidney, it divides into several segmental arteries, which further branch into interlobar arteries. These interlobar arteries pass through the renal columns and give rise to arcuate arteries that run along the border of the renal cortex and the medulla. it splits into segmental arteries, which then divide further into interlobar arteries. These interlobar arteries supply blood to the renal columns in the kidney. Therefore, the renal artery directly conducts oxygenated blood into the kidney from the abdominal aorta.
Finally, the arcuate arteries branch off to form cortical radiate arteries, which further divide into afferent arterioles supplying the nephrons, where filtration of the blood takes place. The renal veins then collect the filtered, now deoxygenated blood, and transport it back to the inferior vena cava, completing the circulatory route through the kidneys.