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': 'Oxaloacetate + Acetyl CoA → Citrate + CoASH. This reaction is \nSelect and explain. \nA. Reversible, B. Irreversible, C. Can be reversed by catalase, D. Competitive', 'role': 'user'}, {'content': 'Answer: B \nExplanation: There are two irreversible steps : (i) Oxaloacetate to citrate, catalyzed by citrate synthase, and (ii) α - ketoglutarate to succinyl CoA, catalyzed by α - ketoglutarate dehydrogenase.', 'role': 'assistant'}]