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: Medicine
[{'content': 'A 5 year old child presents with history of fever off and-on for past 2 weeks and petechial spots all over the body and increasing pallor for past 1 month. Examination reveals splenomegaly of 2 ems below costal margin. The most likely diagnosis is - \nSelect and explain. \nA. Acute leukemia, B. Idiopathic thrombocytopenic purpura, C. Hypersplenism, D. Aplastic anemia', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]