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': 'As per ISO, color of N2O cylinder is – \nSelect and explain. \nA. Blue, B. Black, C. White, D. Red', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Color code of N2O cylinder is blue.', 'role': 'assistant'}]