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': 'ALL L3 morphology is a malignancy arising from which cell lineage – \nSelect and explain. \nA. Mature B cell, B. Precursor B cell, C. Immature T cell, D. Mixed B cell & T cell', 'role': 'user'}, {'content': "Answer: A \nExplanation: Cellular classification of ALL \nFrench-American-British (FAB) system divides ALL into three morphological subtypes.\ni) LI lymphoblasts\n\nMost common type (80-85%)\nCells have scanty cytoplasm and inconspicuous nucleoli.\nHave better prognosis\n\nii) L2 lymphoblasts\n\nCells are large and more pleomorphic in size with more abundant cytoplasm and prominent nucleoli.\n\niii) L3 - lymphoblast\n\nLeast common\nMorphology is identical to urkitt's lymphoma cells i.e., mature B cells with surface immunoglobulin positive.", 'role': 'assistant'}]