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': 'Colour of oxygen cylinder is – \nSelect and explain. \nA. Grey, B. Blue, C. Black with white shoulder, D. Orange', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Oxygen cylinder has black body with white shoulder.', 'role': 'assistant'}]