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
Pyruvate formation is associated with aminoacid 
Select and explain. 
A. Alanine, glycine, histidine, proline, B. Alanine, glycine, methionine, cystidine, C. Phenylalanine, methionine, threonine, proline, D. Alanine, valine, isoleucine, leucine
D: Alanine, valine, isoleucine, leucine
Answer: D: Alanine, valine, isoleucine, leucine 
Explanation: None