Identify the incorrect set$(s)$ among the following periodic trends:

Which of the following statements are true?
$A.$ Unlike $Ga$ that has a very high melting point,$Cs$ has a very low melting point.
$B.$ On Pauling scale,the electronegativity values of $N$ and $Cl$ are not the same.
$C.$ $Ar$,$K^{+}$,$Cl^{-}$,$Ca^{2+}$,and $S^{2-}$ are all isoelectronic species.
$D.$ The correct order of the first ionization enthalpies of $Na$,$Mg$,$Al$,and $Si$ is $Si > Al > Mg > Na$.
$E.$ The atomic radius of $Cs$ is greater than that of $Li$ and $Rb$.
Choose the correct answer from the options given below

Which of the following statements is not correct regarding the classification of elements in the periodic table?

Consider the following:
$(I)$ The order of first ionisation enthalpy of the first three elements of the $3^{rd}$ period is $Mg > Al > Na$
$(II)$ The element with an electronegativity of $3.5$ is chlorine
$(III)$ The order of sizes of ions $Mg^{2+}, Na^{+}, F^{-}$ and $O^{2-}$ is $Mg^{2+} < Na^{+} < F^{-} < O^{2-}$
$(IV)$ The $IUPAC$ name of the element with atomic number $106$ is Bohrium.
The correct statements are

Represent different types of periodic properties in the periodic table.

Which of the following is not correctly matched?