This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc. (W.B.C), Subject name: Pathology
[{'content': 'For which procedure is the following instrument used? \nSelect and explain. \nA. Bone marrow examination, B. Liver biopsy, C. Pleural biopsy, D. Lumbar puncture', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. (a) Bone marrow examination(Ref: Dacie Practical Hematology, 10thed/163; Complete review of Pathology 1st/761)This is a Sahli's bone marrow aspiration needle. (Sahli's needle has a Screw on the side; S for S)Klima's bone marrow aspiration needle (no side screw)", 'role': 'assistant'}]