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
All the following inhibit complex IV and totally arrest respiration except 
Select and explain. 
A. H2S, B. Carbon monoxide, C. Cyanide, D. Dimercaprol
D: Dimercaprol
Answer: D: Dimercaprol 
Explanation: The classic poisons H2S, carbon monoxide, and cyanide inhibit Complex IV and can therefore totally arrest respiration. Reference: Harper; 30th edition; Page no: 132