This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Pharmacology
All of the following are useful in the intravenous therapy for hypertensive emergencies except 
Select and explain. 
A. Fenoldopam, B. Urapidil, C. Enalaprilat, D. Nifedipine
D: Nifedipine
Answer: D: Nifedipine 
Explanation: Ans. (D) Nifedipine(Ref: Katzung 10/e p145, 179: KDT 8th/e p618, 619)Nifedipine can be used rarely for the rapid control of blood pressure but the route of administration is sublingual. Fenoldopam is a D1 agonist used i.v. for hypertensive emergencies whereas urapidil is an a blocker. Enalaprilat (not enalparil) can also be used for the same indication.