This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Neonatal sepsis, Subject name: Pediatrics
[{'content': 'Definitive test for the diagnosis of neonatal sepsis is? \nSelect and explain. \nA. Blood culture, B. Urine culture, C. Immature:Total neutrophil ratio, D. Sepsis screen', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Blood culture: gold standard for diagnosis of sepsis - performed in all cases of suspected sepsis prior to staing antibiotics', 'role': 'assistant'}]