The percentage of covalent character in an ionic bond is determined by which of the following?

Given below are two statements:
Statement $I$: The correct order in terms of bond dissociation enthalpy is $Cl_{2} > Br_{2} > F_{2} > I_{2}$.
Statement $II$: The correct trend in the covalent character of the metal halides is $[SnCl_{4} > SnCl_{2}]$, $[PbCl_{4} > PbCl_{2}]$ and $[UF_{4} > UF_{6}]$.
In the light of the above statements, choose the correct answer from the options given below:

Which ion exhibits the maximum Lewis acid character?

The correct sequence of increasing covalent character is represented by

$A$ metal,$M$,forms chlorides in its $+2$ and $+4$ oxidation states. Which of the following statements about these chlorides is correct?

The charge/size ratio of a cation determines its polarizing power. Which one of the following sequences represents the increasing order of the polarizing power of the cationic species,$K^{+}, Ca^{2+}, Mg^{2+}, Be^{2+}$?