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': 'Cholinergic drug which acts on hea by decrease in levels of cAMP and due to opening of K+ channels is? \nSelect and explain. \nA. Methacholine, B. Oxotremorine, C. Bethanechol, D. DMPP', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. 'a' i.e., Methocholine", 'role': 'assistant'}]