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': 'Heme synthesis requires \nSelect and explain. \nA. Ferrous iron, B. Glycine, C. Succinyl CoA, D. All of these', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Heme is synthesized from succinyl CoA, glycine and Iron (ferrous ion).', 'role': 'assistant'}]