This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: FMGE 2019, Subject name: Anaesthesia
The duration of spinal anaesthesia is based directly on: 
Select and explain. 
A. Dose, B. Height, C. Age, D. Total body fat
A: Dose
Answer: A: Dose 
Explanation: The duration of spinal anesthesia depends upon the dose The level and duration is directly based on dose of the drug