This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
[{'content': 'Calmodulin acts by \nSelect and explain. \nA. Opening of Na+ channels, B. Phosphorylation of myosine by protein kinase, C. Activation of Na+-K+ pump, D. Dephosphorylation by protein kinase', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Calmodulin contains myosin light-chain kinase, which phosphorylates myosin and phosphorylase kinase which activates phosphorylase.(Ref: Textbook of physiology AK JAIN 5th edition page no.20)', 'role': 'assistant'}]