Why do polar substances dissolve in water? water molecules break apart polar molecules. water molecules are attracted to polar molecules and surround them. water molecules react with polar molecules. water molecules press on polar molecules, making the molecules very small.

Polar molecules have " dipole dipole" force of attraction between the molecules consisting of partially positive ion and partially negetive ion.

Water is the best example of polar molecule, having strong "hydrogen bonding" between the atoms of Oxygen (-ve) and Hydrogen(+ve).

When any polar substance dissolved in water, it break down into +ve and -ve ions.

Because of the dipole dipole attraction polar molecules are soluble in water.

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current

i believe the answer is a.