Arrange the following in increasing order of their covalent character.
$CaF_{2}$,$CaCl_{2}$,$CaBr_{2}$,$CaI_{2}$
Choose the correct answer from the options given below.

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:

The most polarisable ion among the following is

Which of the following is the correct decreasing order of the melting points of calcium halides?

Which is the correct decreasing order of polarizability of the following ions?

Out of the following,which one has the highest value of covalent character?