74. Mature red blood cells lack mitochondria. In addition to relying on glycolysis for ATP production, the pentose phosphate pathway (PPP) is also extremely important. What is the most important physiological significance of this pathway for red blood cells? (A) Produces a large amount of ATP for cell membrane pumps. (B) Produces NADPH to maintain glutathione in its reduced state, protecting the cell from oxidative damage. (C) Produces ribose-5-phosphate for de novo nucleic acid synthesis. (D) NADH to be used by lactate dehydrogenase.