Polarity Of Bonds

The interaction between a polar and non-polar molecule is known as dipole-induced dipole interaction. Permanent dipole of the polar molecule induces dipole on the electrically neutral molecule by deforming its electronic cloud.
Thus an induced dipole is developed in the other molecule.

is the correct order of increasing polarising power of the cations. Because according to Fajan?s rules for cations, high charge and small size of the cation have more polarising power that is ability to distort electron density on an cation and induce partial covalent character