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': 'Cytochrome C oxidase is inhibited by \nSelect and explain. \nA. Barbiturate, B. 2, 4-dinitrophanol, C. H2S, D. Rotenon', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Site-III (Complex IV) * Cyanide Inhibits terminal * H2S * Azide transfer of electrons to molecular O2 * Co (Carbon monoxide): Inhibits Cyt. oxidase by combining with O2 binding site. It can be reversed by illumination with light.Ref: MN Chatterjea Textbook of Medical Biochemistry, 8th edition, page no: 143', 'role': 'assistant'}]