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
A 30–year-old male, Rajinder presents to OPD with fatigue, muscle weakness, and headache. His blood pressure is 170/120 mmHg and his heart rate is 100/min. Laboratory evaluation reveals hypokalemia, metabolic alkalosis and decreased plasma renin activity. On CT scan, a mass was noted on the left suprarenal gland. The patient was prescribed a drug for a few weeks and the symptoms subsided. Laboratory values and blood pressure returned to normal values. The likely drug given to this patient is? 
Select and explain. 
A. Clonidine, B. Propranolol, C. Hydrochlorothiazide, D. Spironolactone
D: Spironolactone
Answer: D: Spironolactone 
Explanation: None