Answer:
A. complex I
B. complex II
Explanation:
Complex I of the electron transport chain is NADH dehydrogenase. It has FMN and Fe-S prosthetic groups. Complex II of ETC is the succinate dehydrogenase. It also has FAD and Fe-S as prosthetic groups. Both complexes I and II lack any type of heme as a prosthetic group. Complex III (cytochrome c oxidoreductase), cytochrome c and complex IV have heme cofactors. Heme A is present in a-type cytochromes while heme C is present in c-type cytochromes.
