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
Which one of the following increases the strength and reduce viscosity of agar hydrocolloid impression material: 
Select and explain. 
A. Borax, B. Water, C. Sulfates, D. Carbonates
A: Borax
Answer: A: Borax 
Explanation: None