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: Biochemistry
The dielectric constant of water  is  ___. 
Select and explain. 
A. 105, B. 78.5, C. 30, D. 60
B: 78.5
Answer: B: 78.5 
Explanation: Water, a strong dipole, has high dielectric constant.
The dielectric constant for water is 78.5.
It decreases the force of attraction between charged and polar species relative to water free environments with lower dielectric constants.