What is the decreasing order of the ionization energy for the following elements?

Which among the following elements has the lowest value of $IE_1$?

In the given graph,which point represents an alkali metal with the least atomic number (Period number $= 3$)?

Given below are two statements:
Statement $I$: The decrease in first ionization enthalpy from $B$ to $Al$ is much larger than that from $Al$ to $Ga$.
Statement $II$: The $d$ orbitals in $Ga$ are completely filled.
In the light of the above statements,choose the most appropriate answer from the options given below:

The correct order of $C$, $N$, $O$ and $F$ in terms of second ionisation potential is

Consider the following ionisation reactions:

$A_{(g)} \to A^{+}_{(g)} + e^-, \ A_1$	$B_{(g)} \to B^{+}_{(g)} + e^-, \ B_1$
$B^{+}_{(g)} \to B^{2+}_{(g)} + e^-, \ B_2$	$C_{(g)} \to C^{+}_{(g)} + e^-, \ C_1$
$C^{+}_{(g)} \to C^{2+}_{(g)} + e^-, \ C_2$	$C^{2+}_{(g)} \to C^{3+}_{(g)} + e^-, \ C_3$

If the monovalent positive ion of $A$,divalent positive ion of $B$,and trivalent positive ion of $C$ have zero electrons,then which of the following is the incorrect order of the corresponding $I.E.$?