Answer:
The CORRECT ANSWER IS B.
B. Unlike the other countercurrent systems, a countercurrent multiplier system expends energy in active transport.
Step-by-step explanation:
The countercurrent multiplier system involving the loop of Henle uses up energy in the form of ATP to actively conduct NaCl out of the filtrate in the upper region of the ascending limb of the loop. This energy in the form of ATP that is being used uniquely differentiates a countercurrent multiplier system from the different forms of countercurrent systems.