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
Vapour concentration in a breathing system is monitored by all except 
Select and explain. 
A. Infrared gas analysis, B. Gas chromatography, C. Ultraviolet gas analysis, D. Paramagnetism
B: Gas chromatography
Answer: B: Gas chromatography 
Explanation: Mass spectrometry, infrared gas analysis, ultraviolet gas analysis and paramagetism are used to monitor vapour concentration in a breathing system.