Task: Question Answering
Input (English): Question: What enzyme is present in complex II that participates in oxidative phosphorylation? 
 Options:  <1> Coenzyme Q: cytochrome c oxidoreductase. <2> NADH dehydrogenase. <3> Succinate-coenzyme Q reductase. <4> ATP synthase. <5> Cytochrome c oxidase.
Output (English): 3