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': 'Which of the following produces the least damage to blood elements – \nSelect and explain. \nA. Disc oxygenator, B. Membrane oxygenator, C. Bubble oxygenator, D. Screen oxygenator', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Hematological advantages of membrane oxygenater over bubble oxyenators :- Less trauma to RBCs, platelets & WBCs and less protein denaturation.', 'role': 'assistant'}]