This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Active metabolite of Spironolactone  is: 
Select and explain. 
A. Gluconalactone, B. Eplerenone, C. Canrenone, D. Triamterene
C: Canrenone
Answer: C: Canrenone 
Explanation: Spironalactone is aldosterone antagonist and Canrenone is the active metabolite.