Mammalian Nephrons Are Different from Amphibian Nephrons in That Only

Mammalian nephrons are different from amphibian nephrons in that only mammalian nephrons

A) filter blood.
B) actively transport sodium and chloride ions back into body tissues.
C) produce urine with the same concentration as that of blood.
D) employ tubular secretion and reabsorption to control urine composition.
E) use a countercurrent multiplication mechanism.