Which of the following halides has the highest melting point?

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

Which of the following is in the increasing order of the ionic character?

$AgF, AgCl, NaCl, NaBr, NaI$ are colourless but $AgBr$ and $AgI$ are coloured because

The combination of which of the following gives an ionic compound with maximum covalent character?

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: