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
All are true about thiopentone except – 
Select and explain. 
A. NaHCO3 is a preservative, B. Contraindicated in porphyria, C. Agent of choice in shock, D. Has cerebroprotective action
C: Agent of choice in shock
Answer: C: Agent of choice in shock 
Explanation: Thiopentone causes hypotension → contraindicated in shock & hypotensive states.