Answer:
The correct answer is A. The blood vessels of the renal medulla that run alongside the nephron loops are the vasa recta.
Step-by-step explanation:
In anatomy, the descending vasa recta or descending straight vessel is an artery of the renal tissue, originating from the efferent arterioles, arched artery, and interlobar artery. They are so named because they follow a straight and descending trajectory from the cortex to the deepest portions of the renal medulla.