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: Anaesthesia
Which of the following i.v anaesthetic agent suppresses cortisol synthesis 
Select and explain. 
A. Propofol, B. Ketamine, C. Etomidate, D. Thiopentone
C: Etomidate
Answer: C: Etomidate 
Explanation: Etomidate is known to cause adrenocortical suppression on long term infusion.