Which of These Statements Does NOT Refer to Urea

Multiple Choice

Which of these statements does NOT refer to 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 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 amount is eliminated from the plasma.