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
Aminoacid that enters the TCA cycle for gluconeogenesis & Ketogenic in nature 
Select and explain. 
A. Pheylalanine, B. Alanine, C. Glycine, D. Serine
A: Pheylalanine
Answer: A: Pheylalanine 
Explanation: Phenylalanine is both glucogenic (gluconeogenic) and ketogenic.