The atomic numbers of elements $A, B, C$ and $D$ are $Z-1, Z, Z+1$ and $Z+2$,respectively. If $B$ is a noble gas,choose the correct statements from the following:
$(1)$ $A$ has high electron affinity
$(2)$ $C$ exists in $+2$ oxidation state
$(3)$ $D$ is an alkaline earth metal

Assign true $(T)$ or false $(F)$ for the following statements and select the correct option for your answer:
$(I)$ $I.P.$ of $O_{(g)}$ is less than $I.P.$ of $O^{-}_{(g)}$
$(II)$ $I.P.$ of $Ne_{(g)}$ is greater than $I.P.$ of $Ne^{+}_{(g)}$
$(III)$ $E.A.$ of $O^{+}_{(g)}$ is greater than $E.A.$ of $O_{(g)}$
$(IV)$ $I.P.$ of $N_{(g)}$ is greater than $I.P.$ of $N^{+}_{(g)}$

Among the elements $B$,$Al$,$C$,and $Si$,
$(a)$ which element has the highest first ionisation enthalpy?
$(b)$ which element has the most metallic character? Justify your answer in each case.

Which of the following statements is incorrect?

Point out the wrong statement: On moving horizontally from left to right across a period in the periodic table

Given below are two statements:
Statement $I$ : The correct order of first ionization enthalpy values of $Li, Na, F$ and $Cl$ is $Na < Li < Cl < F$.
Statement $II$ : The correct order of negative electron gain enthalpy values of $Li, Na, F$ and $Cl$ is $Na < Li < F < Cl$.
In the light of the above statements,choose the correct answer from the options given below :