This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
Which of these enzymes does not play a role in the generation of proton gradient during electron transport? 
Select and explain. 
A. NADH oxidase, B. Succinate CoQdehydrogenase, C. Cytochromeoxidase, D. Cytochromeb-c1
B: Succinate CoQdehydrogenase
Answer: B: Succinate CoQdehydrogenase 
Explanation: Ref:    Harper’s ‘Illustrated Biochemistry’; 27/e, pg103