Which of the following ionisation energy values for calcium show a sudden increase ?

Solution :
$$\eqalign{ & Ca = 3{s^2}3{p^6}4{s^2} \cr & C{a^{2 + }} = 3{s^2}3{p^6}4{s^0} \cr} $$
( Stable noble gas configuration )
Hence, there would be sudden increase in $$I{E_3}$$  value.