This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolic disorders, Subject name: Pediatrics
[{'content': 'A 3 day child vomits everything he feeds, has a distened abdomen & diarrhoea. The urine is positive for benedicts test for reducing substance. The substance in urine is \nSelect and explain. \nA. Sucrose, B. Glucose, C. Galactose, D. Fructose', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Galactosemia caused by the deficiency of enzyme GALT(galactose-1-phosphate uridyl transferase).Patients appear normal at bih,but by 3-4 days of breast milk,/formula feeding,show life threatening disease with vomiting,diarrhoea,poor weight gain,hepatic and renal manifestations and cataract.In case if suspected galactosemia,the urine should be tested simultaneously with Benedict reagent and by glucose-oxidase method.A negative dipstick by glucose oxidase method with positive Benedict reaction indicates nonglucose reducing substances,like galactose. Reference:Essential pediatrics-Ghai,8th edition,page no:657.', 'role': 'assistant'}]