This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anaesthesia, Subject name: Pharmacology
The segmental level of spinal anaesthesia depends on: 
Select and explain. 
A. Volume of the local anaesthetic injected, B. Specific gravity of the local anaesthetic solution, C. Posture of the patient, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: * Factors affecting the height of block :- -- Volume of drug -- Baricity (Ratio of specific gravity of an agent to that of CSF). -- Position of the patient -- Intra-abdominal pressure -- Curvature of spine * Factors affecting duration of block :- -- Dose -- Concentration - - Drug (LA used) -- Added vasoconstrictors