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
Inhibitor of Complex I of ETC- 
Select and explain. 
A. H2S, B. 2, 4 DND, C. Rotenone, D. BAL
C: Rotenone
Answer: C: Rotenone 
Explanation: Ans. is 'c' i.e., Rotenone Inhibitors of Electron transport chain (Respiratory chain)o Complex I:- Barbiturates (amoborbital), piercidin A, rotenone, ehlorpromazine, guanithidine.o Complex II:- Carboxin, TTFA, malonate.o Complex III:- Dimercaprol, BAL, actinomycin A, Naphthyloquinone.o Complex IV (cytochrome c oxidase) Carbon monoxide (CO), cyanide (CN-), H2S, azide (N3 )