This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Basics of amino acids, Subject name: Biochemistry
[{'content': 'Non-protein amino acid is \nSelect and explain. \nA. Aspaate, B. Histidine, C. Ornithine, D. Tyrosine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Non-protein amino acids are those found in our body but not incorporated into proteins. They are not coded by codons. Example of non-protein amino acids: Ornithine Citrulline Homocysteine Beta-alanine GABA Sarcosine Homoserine', 'role': 'assistant'}]