Which among the following species has the highest ionisation potential?

As one moves along a given row in the periodic table,ionization energy

The successive ionization energy values for an element $X$ are given below:
$(i)$ $1^{st}$ ionization energy $= 410 \ kJ \ mol^{-1}$
$(ii)$ $2^{nd}$ ionization energy $= 820 \ kJ \ mol^{-1}$
$(iii)$ $3^{rd}$ ionization energy $= 1100 \ kJ \ mol^{-1}$
$(iv)$ $4^{th}$ ionization energy $= 1500 \ kJ \ mol^{-1}$
$(v)$ $5^{th}$ ionization energy $= 3200 \ kJ \ mol^{-1}$
Find the number of valence electrons in the atom $X$.

Match List-$I$ with List-$II$ with correct code:

List-$I$ ($IE_1, IE_2, IE_3$ in $kJ \ mol^{-1}$)	List-$II$ (Element)
$A$. $1510$	$1$. $H$
$B$. $495, 6500, 10200$	$2$. $Li$
$C$. $840, 1630, 13100$	$3$. $Be$
$D$. $600, 2050, 3100$	$4$. $B$

What is the order of the first,second,and third ionization enthalpies of an element?

The successive ionisation enthalpies of an element $X$ in $(kJ \ mol^{-1})$ are $1012$,$1907$,$2955$,$4955$,$6275$ and $21,260$ respectively. The element $X$ is: