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: Psychiatry
Visual analogue scale (VAS) most widely used to measure 
Select and explain. 
A. Sleep, B. Sedation, C. Pain intensity, D. Depth of Anaesthesia
C: Pain intensity
Answer: C: Pain intensity 
Explanation: C i.e. Pain intensity