This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Childhood tumors, Subject name: Pediatrics
ALL L3 morophology is a malignancy arising from which cell lineage 
Select and explain. 
A. Mature B cell, B. Precursor B cell, C. Immature T cell, D. Mixed B cell & T cell
A: Mature B cell
Answer: A: Mature B cell 
Explanation: ALL L3 is arising from mature B cells.Only 1-2% patients with ALL show L3 morphology in which cells are large,have deep cytoplasmic basophilia and prominent vacuolation.These cells show surface immunoglobulin and should be treated as Burkitt lymphoma. Reference:Essential pediatrics-Ghai,8th edition,page no:600.