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': 'All are second messengers except: \nSelect and explain. \nA. Cyclic AMP, B. Guanylyl cyclase, C. Diacylglycerol, D. Inositol triphosphate', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Remember that guanylyl cyclase is an enzyme while\xa0cGMP is a secondary messenger\nTypes of second messengers\nThere are 3 basic types of secondary messenger molecules:\n1. Hydrophobic\n\nDAG\nIP3\nPhosphotidylinositol\n\n2. Hydrophilic\n\ncAMP\ncGMP\n\n3. Gases\n\nNO\nCO', 'role': 'assistant'}]