This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Breathing Systems, Subject name: Anaesthesia
[{'content': 'The names Brechner and Bethune are associated with which of the following devices? \nSelect and explain. \nA. Precordial Doppler, B. Transesophageal echocardiography, C. Plethysmography, D. End tidal capnography', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. d. End tidal capnography (Ref: Bethune, R. W. M., and Brechner, V. L. (1968). Detection of venous air embolism by carbon dioxide monitoring. Anesthesiology, 29, 178)Brechner and Bethune are associated with end-tidal capnography.', 'role': 'assistant'}]