Left Panel
A is an acid. Not the answer.
B is correct. That would be a base. But it is not an Arrhenius base. Keep reading.
C that is exactly what an Arrhenius base is.
D. No an acid of some sort would accept OH ions.
Right Panel
D is concentrated and it is also a weak base. Good cleaning fluid. Smells awful but it works.
Answer:
It was built to house the employees of the Chernobyl Nuclear Power Plants located 4 kilometers away and became the ninth nuclear city in the Soviet Union.
Explanation:
K is Potassium
Cl is Chlorine
There are 2 elements.