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
[{'content': 'Which of the following drugs shows the phenomenon of vasomotor reversal of Dale after administration of an α adrenergic blocker ? \nSelect and explain. \nA. Adrenaline, B. Noradrenaline, C. Isoprenaline, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]