A)NAD⁺ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle. B)NAD⁺ has more chemical energy than NADH. C)NAD⁺ is oxidized by the action of hydrogenases. D)NAD⁺ can donate electrons for use in oxidative phosphorylation. E)In the absence of NAD⁺, glycolysis can still function.