Which of These Statements Does NOT Correctly Describe Urea

Which of these statements does NOT correctly describe urea?

A) It is a waste product resulting from the breakdown of protein.
B) It is passively reabsorbed at the end of the proximal tubule down a urea concentration gradient created by the osmotic-induced reabsorption of water from the proximal tubule.
C) Recycling between the late portion of the collecting tubule and the long loops of Henle contributes to medullary hypotonicity.
D) Only half the filtered urea is eliminated from the plasma.