This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Pathology
[{'content': 'Marker for hairy cell leukaemia is? \nSelect and explain. \nA. CD30, B. CD 103, C. CD 1, D. CD4', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Hairy cell leukemia express CD 19 ,CD2O, CD22 antigen. In addition to Bcell markers they are also positive for CD11,CD25,CD103 Reference : Harsh Mohan textbook of pathology, 7th edition.Pg no.358', 'role': 'assistant'}]