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': 'A patient of more than 70 years, presented with generalized lymphadenopathy. WBC count was 20,000/ mm3 and blood film showed >70% mature looking lymphocytes. Next investigation that should be done \nSelect and explain. \nA. LN biopsy, B. Peripheral Immunophenotyping, C. Bone marrow aspiration, D. Peripheral blood cytogenetics', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. b. Peripheral Immunophenotyping A patient of more than 70 years, presented with generalized lymphadenopathy. WBC count was 20,000/mm3 and blood film showed >70% mature looking lymphocytes. This clinical situation is suggestive of CLL Harrison says "Differential diagnosis of typical B cell CLL is extensive. Immunophenotyping will eliminate the other T-cell disorders and can often help so other B-cell malignancies."', 'role': 'assistant'}]