This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pharmacology, Subject name: Pharmacology
[{'content': 'The action of Adrenergic a2 receptors and b1 receptors on adenyl cyclase? \nSelect and explain. \nA. Stimulate; Stimulate, B. Stimulate; Inhibit, C. Inhibit; Inhibit, D. Inhibit; Stimulate', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Most of the receptors are G protein-coupled receptors .Among G protein-coupled receptors, Inhibitory receptors are Alpha 2, M2 etcStimulatory receptors are all beta receptors (beta 1, beta2 and beta 3) Ref: H.L Sharma 3rd ed. Pg: 64', 'role': 'assistant'}]