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: Anatomy
[{'content': 'In epidural lumbar puncture, all structure are pierced except - \nSelect and explain. \nA. Posterior longitudinal ligament, B. Ligamentum flavum, C. Interspinous ligament, D. Supraspinous ligament', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Structure pierced during lumbar puncture (from outside in) are :-\n\nSkin → Subcutaneous tissue → Supraspinous & interspinous ligament → Ligament flavum → Dura matter → Arachnoid matter.', 'role': 'assistant'}]