question: Q:During oxidative phosphorylation, the energy needed to drive ATP synthesis comes from one source. Which of the following statements states the immediate source of that energy?? 
  A:Electrons flow down an electron transport chain as they are attracted to oxygen.;B:The transfer of a phosphate group to ADP is exergonic.;C:The bonding of electrons to oxygen at the end of the chain releases energy.;D:The proton gradient across the membrane where the ATP synthase is embedded represents potential energy.