Column - I	Column - II
A) Benzene	1) Good conductor
B) Water	2) Non polar solvent
C) Solid NaCl	3) Polar solvent
D) Aqueous NaCl	4) Bad conductor

I)  In Benzene ( ), there are six C-H bonds and six C-C bonds.  All bonds are non polar bonds.  Due to absence of ions, benzene is a non polar solvent.

II)  In water ( ), there are two O-H bonds. These two bonds are polar covalent bonds.  Due to presence of   and ions, water is a polar solvent.

III)  In Solid NaCl, the bond between and is ionic bond. In solid state, these ions are tightly packed by strong electro static force of attraction. Due to absence of free moving ions, solid NaCl is a bad conductor of electricity. 

IV)  In Aqueous NaCl,  and ions are freely  moved  in water. Due to these free moving ions, aqueous NaCl is a good conductor of electricity.