This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory chain, Subject name: Biochemistry
[{'content': 'Total number of dehydrogenases Krebs cycle \nSelect and explain. \nA. 3, B. 2, C. 4, D. 5', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Isocitrate dehydrogenase (ICD) enzyme succinate dehydrogenase Malate dehydrogenase a-ketoglutarate dehydrogenaseRef: MN Chatterjea Textbook of Medical Biochemistry, 8th edition, page no: 339', 'role': 'assistant'}]