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
[{'content': 'Gas stored in liquid form is? \nSelect and explain. \nA. CO2, B. N20, C. Cyclopropane, D. 2', 'role': 'user'}, {'content': 'Answer: B \nExplanation: N20 REF: Morgan 4th ed p. 20 NITROUS OXIDE: Stored in blue cylinder Pin index - 3, 5 Liquid gas 745 psi pressure 1590 lit is the volume', 'role': 'assistant'}]