The diagram below outlines the metabolic pathway of anaerobic respiration in mammalian skeletal muscle cells.
Based on this pathway, what is the primary biological purpose of converting pyruvate to lactate, and what is the net yield of ATP and reduced NAD (NADH) per molecule of glucose oxidized under these anaerobic conditions?
To regenerate NAD+NAD^+NAD+; net yield of 2 ATP2\text{ ATP}2 ATP and 0 NADH0\text{ NADH}0 NADH
To regenerate NAD+NAD^+NAD+; net yield of 2 ATP2\text{ ATP}2 ATP and 2 NADH2\text{ NADH}2 NADH
To regenerate NADHNADHNADH; net yield of 4 ATP4\text{ ATP}4 ATP and 2 NADH2\text{ NADH}2 NADH
To regenerate NAD+NAD^+NAD+; net yield of 36 ATP36\text{ ATP}36 ATP and 0 NADH0\text{ NADH}0 NADH