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 is the anesthetic agent of choice in a case of status asthmaticus? 
Select and explain. 
A. Ketamine, B. Thiopentone, C. Ether, D. Nitrous Oxide
A: Ketamine
Answer: A: Ketamine 
Explanation: Ketamine along with adjunctive therapy is the standard therapy in the treatment of children with status asthmaticus and impending respiratory failure. Ketamine cause bronchodilation through the inhibition of vagal tone, release of endogenous catecholamines and by direct muscle relaxation.