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: Pediatrics
[{'content': 'In maple syrup urine disease FeCl3 test with urine gives ____ color – \nSelect and explain. \nA. Green, B. Blue, C. Black, D. Red', 'role': 'user'}, {'content': "Answer: B \nExplanation: Diagnosis \n\nIs usually suspected because of the peculiar odour of maple syrup found in the body fluids - urine, sweat, cerumen etc.\nDiagnosis is continued by amino acid analysis showing marked elevation in plasma level of leucine, isoleucine, valine and alloisoleucine (a stereoisomer of isoleucine not normally found in blood) and depression of alanine. Leucine levels are usually higher than those of other three amino acids.\nUrine contains high levels of leucine, isoleucine and valine and their respective ketoacids.\nThe keto acids may be detected by adding a few drops 2-4 dinitrophenylhydrazine (DNPH) reagent which produces a yellow precipitate in a positive test.\nFerric chloride gives navy blue colour with the patient's urine.", 'role': 'assistant'}]