This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pediatrics
[{'content': 'A baby presents with diarrhea and perianal diaper area redness. Diagnosis is \nSelect and explain. \nA. Lactose intolerance, B. Shigella diarrhea, C. Salmonella, D. Fungal', 'role': 'user'}, {'content': "Answer: A \nExplanation: In Lactose intolerance, there is a deficiency of the enzyme lactaseSo there is no natural breakdown of lactose - a carbohydrate present in milkThis causes diarrheaThe stool contains reducing sugar which causes perianal excoriation(Refer: Nelson's Textbook of Pediatrics, SAE, 1st edition, pg no. 1876)", 'role': 'assistant'}]