Identify the renal column and where is it located, and does the nephron or blood vessel go thru it what is its salt concentration?

A) The renal column is located in the medulla of the kidney, and both nephrons and blood vessels pass through it; its salt concentration varies depending on hydration levels.
B) The renal column is located in the cortex of the kidney, and only blood vessels pass through it; its salt concentration remains constant.
C) The renal column is located between the renal pyramids of the kidney, and only nephrons pass through it; its salt concentration is higher than in other kidney structures.
D) The renal column is located in the renal pelvis of the kidney, and neither nephrons nor blood vessels pass through it; its salt concentration is lower than in other kidney structures.