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
Intact peptide bond is necessary for which test: 
Select and explain. 
A. UV diffraction, B. Ninhydrin, C. Diazo reaction, D. All
B: Ninhydrin
Answer: B: Ninhydrin 
Explanation: B i.e. NinhydrinAmino acids can be detected and quantified by reaction with ninhydrin after seperation of amino acid from mixtures. The test requires intact peptide bondsQ.