Which Statement Is FALSE

Multiple Choice

Which statement is FALSE?

A) The osmolarity of the medullary interstitial fluid always equilibrates with the descending limb of the loop of Henle.
B) ACE inhibitor drugs promote diuresis by blocking the conversion of angiotensin I into angiotensin II.
C) If a substance is filtered and secreted but not reabsorbed, its plasma clearance rate is always less than the GFR.
D) A plasma clearance of 135 mL/min for a substance when the GFR is 125 mL/min indicates that net secretion of the substance occurs.