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: Physiology
[{'content': 'CAMP acts through: \nSelect and explain. \nA. Activation of protein kinase, B. Activation of adenylate cyclase, C. Ca2+ release., D. All', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e., Activation of protein kinase', 'role': 'assistant'}]