for any particular electron donor, the most free energy will be released when molecular oxygen serves as the final electron acceptor because . . . choose one:a. the concentration of oxygen gas is higher than the concentrations of most other feasible electron acceptors.b. molecular oxygen is a stronger oxidizing agent than most other available electron acceptors.c. molecular oxygen has a higher molecular weight than most other available electron acceptors.d. molecular oxygen donates electrons more readily than most other available electron acceptors.