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': 'The most important constituent in soda lime for reabsorption of CO2 in a closed circuit is – \nSelect and explain. \nA. Sodium hydroxide, B. Barium hydroxide, C. Calcium hydroxide, D. Potassium hydroxide', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Sodalime contains Ca(OH)2 (94%), NaOH (5%), KOH (< 1%), Silica, indicator and moisture.', 'role': 'assistant'}]