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
Which of the following drug decreases plasma renin activity? 
Select and explain. 
A. Enalapril, B. Nefidipine, C. Hydralazine, D. Clonidine
D: Clonidine
Answer: D: Clonidine 
Explanation: Ans. is 'd' i.e., Clonidine o Drugs which increase plasma renin activity (Diuretics, vasodilators, CCBs, ACE inhibitors) may be combined with drugs which lower plasma renin activity (sympatholytic drugs - b-blockers, clonidine, methyl dopa).