This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hypeension, Arrhythmias, Dyslipidemia, Subject name: Pharmacology
[{'content': 'Which of the following calcium channel blocker has a predominant peripheral action? \nSelect and explain. \nA. Verapamil, B. Diltiazem, C. Nifedipine, D. Nor-verapamil', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Three groups of CCBs include: Phenylalkylamines (verapamil, nor-verapamil) Benzothiazepines (diltiazem) Dihydropyridines (nifedipine, nicardipine, nimodipine, nisoldipine, felodipine and amlodipine). By inhibiting the calcium channels, these agents result in vasodilation and decreased activity of the hea (decrease hea rate, AV conduction and contractility). Dihydropyridine (DHP) group has little direct cardiac activity and acts mainly on blood vessels, therefore are also called peripherally acting CCBs.', 'role': 'assistant'}]