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: Biochemistry
[{'content': 'Enzyme regulated by phosphorylation are all except \nSelect and explain. \nA. Glucokinase, B. Glycogen synthase, C. Glycogen phosphorylase, D. Citrate lyase', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Examples of Mammalian Enzymes Whose Catalytic Activity Is Altered by Covalent Phosphorylation-Dephosphorylation:', 'role': 'assistant'}]