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: Dental
Major drawback of pro-root MTA is its increased setting time which is decreased by addition of ? 
Select and explain. 
A. 3% of NaOH, B. 3% NaCl, C. 5% CaCl, D. Distilled Water
C: 5% CaCl
Answer: C: 5% CaCl 
Explanation: None