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: Pharmacology
In spinal anaesthesia the drug is deposited between? 
Select and explain. 
A. Dura and arachnoid, B. Pia and arachnoid, C. Dura and veebra, D. Into the cord substance
B: Pia and arachnoid
Answer: B: Pia and arachnoid 
Explanation: Ans. is 'b' i.e., Pia and arachnoid matter o In spinal anaesthesia LA is injected into subarachnoid space (space between pia matter and arachnoid matter). o Structure pierced during SA (from outside in) - Skin - Subcutaneous tissue --> Supraspinous & intraspinous ligament --> Ligamentum falvum --> Duramater - Arachnoidmater.