This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Adrenal, Subject name: Pharmacology
Aldosterone is known to cause sodium retention. Its Na+ retaining action is exeed on which pa of the nephron? 
Select and explain. 
A. Proximal convoluted tubule, B. Ascending limb of loop of Henle, C. Collecting ducts, D. Early distal convoluted tubule
C: Collecting ducts
Answer: C: Collecting ducts 
Explanation: * Aldosterone is the principal mineralocoicoid. It stimulates the reabsorption of Na+ and excretion of K+ and H+ by its action on late distal tubules and collecting ducts.