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: Surgery
[{'content': 'A 40 year male presented with massive splenomegaly. There was mild hepatic enlargement also. Peripheral blood film shows cells with hair like projections; which are positive for CD 25 and CD 103 and negative for CD 23. The likely diagnosis is a : \nSelect and explain. \nA. Precursor B - cell neoplasm, B. Peripheral B - cell neoplasm, C. Precursor T-cell neoplasm, D. Peripheral T-cell neoplasm', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Peripheral B - cell neoplasm Hairy cells on peripheral blood smear and CD 103 positivity are diagnostic of hairy cell leukemia which is a peripheral B cell neoplasm.', 'role': 'assistant'}]