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': "An 8 year old child with acute lymphadenopathy, fever, 20% lymphocytosis indicates the diagnosis of – \nSelect and explain. \nA. Infectious mononucleosis, B. ALL, C. Pulmonary Koch's, D. a–hemolytic Streptococcal infection", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]