This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of carbohydrate, Subject name: Biochemistry
[{'content': 'Co-factor for phosphofructokinase is \nSelect and explain. \nA. Mg +2, B. Mn +2, C. Fe +2, D. Zn', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Many of the glycolytic enzymes are sensitive to Mg2+. The most impoant effect is due to MgATP2-being a cofactor for a number of these enzymes while other chelation forms are inactive or inhibitory. The means by which Mg2+ and Mg2+ chelates of adenine nucleotides regulate the most impoant glycolytic enzymes--hexokinase, phosphofructokinase, aldolase, phosphoglycerate kinase, and pyruvate kinaseRef: DM Vasudevan, 7th edition', 'role': 'assistant'}]