Which of These Statements Does NOT Correctly Describe the Countercurrent

Multiple Choice

Which of these statements does NOT correctly describe the countercurrent system?

A) The loops of Henle of juxtamedullary nephrons are responsible for establishing a vertical osmotic gradient in the interstitial fluid of the renal medulla by countercurrent multiplication.
B) The active NaCl pump of the ascending limb of Henle's limb can establish a 200 mOsm/litre concentration difference between the ascending and descending limbs at any given horizontal level.
C) By means of countercurrent exchange, the vasa recta preserve the vertical osmotic gradient while supplying blood to the medullary tissue.
D) The collecting tubules of all nephrons utilize the driving force of the vertical osmotic gradient to accomplish variable H₂O reabsorption under the control of vasopressin, which governs their permeability.