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: Pathology
[{'content': 'B cell ALL is due to which of the following? \nSelect and explain. \nA. T cells, B. Immature B cells, C. Immature T cells, D. Both T and B cells', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B cell ALL is due to immature B cells.', 'role': 'assistant'}]