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': 'One of the following molecules acts as a mobile electron carrier in the respiratory chain \nSelect and explain. \nA. Ubiquinone, B. FADH2, C. FeS, D. Cytochrome b', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ref: Harper&;s Biochemistry; 30th edition; Chapter 13; The Respiratory Chain & Oxidative Phosphorylation', 'role': 'assistant'}]