In oxidative phosphorylation, why does $F_A{D}_2$ oxidation yield less ATP than $NADH$ oxidation?

• A. $F_A{D}_2$ transfers electrons directly to Complex IV, skipping Complexes I through III, which eliminates proton pumping.
• B. $F_A{D}_2$ inhibits ATP synthase, reducing the coupling of the proton gradient to ATP formation.
• C. $F_A{D}_2$ is oxidized in the cytosol and requires a shuttle that consumes ATP before electrons enter the electron transport chain.
• D. $F_A{D}_2$ donates electrons to Complex II, bypassing Complex I, so fewer protons are pumped across the inner mitochondrial membrane.

Answer: (D)