This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Structure and function of protein, Subject name: Biochemistry
Cytochrome oxidase in oxidative phosphorylation is inhibited by 
Select and explain. 
A. CO, B. H2S, C. Rotenone, D. Amobarbital
A: CO
Answer: A: CO 
Explanation: Cyanide and carbon monoxide kill because they disrupt the physiologic function of the heme proteins cytochrome oxidase and hemoglobin,respectively.Ref: Harper&;s Biochemistry; 30th edition; Chapter 6 Proteins: Myoglobin & Hemoglobin