This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
Co-enzymes of pyruvate dehydrogenase are all except 
Select and explain. 
A. Biotin, B. NAD, C. FAD, D. CoA
A: Biotin
Answer: A: Biotin 
Explanation: None