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: Skin
[{'content': 'The most impoant 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: Ans. c. Calcium hydroxide', 'role': 'assistant'}]