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
[{'content': 'Biuret reaction is specific for \nSelect and explain. \nA. –CONH-linkages, B. –CSNH2 group, C. –(NH)NH2 group, D. All of these', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Biuret Reaction : Cupric ions in an alkaline medium form a violet color with peptide bond nitrogen (Schiff, 1896). This needs a minimum\xa0of two peptide bonds, and so individual amino acids and dipeptides will not answer this test.\nReference: Vasudevan 7th\xa0 ed, pg 31', 'role': 'assistant'}]