Formation of a Highly Concentrated Urine Is Dependent Upon

Formation of a highly concentrated urine is dependent upon

A) Elevated levels of vasopressin in the plasma
B) Elevated levels of aldosterone in the plasma
C) Active transport of Na⁺ and Cl^- by the descending limb of the loops of Henle
D) Elevated levels of vasopressin in the plasma and elevated levels of aldosterone in the plasma
E) All of the choices are correct