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
The substance is soda lime that acts as catalyst is 
Select and explain. 
A. Sodium hydroxide, B. Potassium hydroxide, C. Calcium hydroxide, D. Silica
B: Potassium hydroxide
Answer: B: Potassium hydroxide 
Explanation: Potassium hydroxide acts as catalyst for generation of sodium carbonate.