This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anaesthesia, Subject name: Pharmacology
Anesthetic drug which has highest minimum alveolar concentration is 
Select and explain. 
A. Nitrous oxide, B. Isoflurane, C. Desflurane, D. Xenon
A: Nitrous oxide
Answer: A: Nitrous oxide 
Explanation: MAC is measure of potency of inhalational anesthetic drug which is minimum concentration required to produce immobility in 50% individuals Nitrous oxide has lowest potency with highest MAC value