This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of carbohydrate, Subject name: Biochemistry
All of the following take pa in oxidative phosphorylation except 
Select and explain. 
A. NADH, B. FADH2, C. NADPH, D. ATP
A: NADH
Answer: A: NADH 
Explanation: The NADPH system is responsible for generating free radicals in immune cellsNADPH is also used for anabolic pathways, such as lipid synthesis, cholesterol synthesis, and fatty acid chain elongation.Reference: