Which of the following represents the correct order of increasing first ionization enthalpy for Ca, Ba, S, Se and Ar?

The correct option is B

Ba < Ca < Se < S < Ar

Ionisation energy increases along a period from left to right and decreases down a group. The position of given elements in the periodic table is as
$\begin{array}{ccc}GroupNo.2& 16& 18\\ Ca& S& Ar\\ Ba& Se& \end{array}$
Thus, the order of increasing $\Delta H_{I{E}_1}$ is
Ba < Ca < Se < S < Ar