Consider the following four elements, which are represented according to long form of periodic table.

Here W, Y and Z are left, up and right elements with respect to the element 'X' and 'X' belongs to 16th group and 3rd period. Then according to given information the incorrect statement regarding given elements is:

1. Maximum electronegativity :Y             

2. Maximum catenation property :X

3. Maximum electron affinity :Z               

4. Y exhibits variable covalency

The process that is not endothermic in nature, is : 

1. $A{r}_{\left(g\right)}<mspace\; width="1em"></mspace>+<mspace\; width="1em"></mspace>e^{-}<mspace\; width="1em"></mspace>\to <mspace\; width="1em"></mspace>A{r}_{\left(g\right)}^{-}$

2. $N{a}_{\left(g\right)<mspace\; width="1em"></mspace>}\to <mspace\; width="1em"></mspace>N{a}_{\left(g\right)}^{+}<mspace\; width="1em"></mspace>+<mspace\; width="1em"></mspace>e^{-}$

3. $H_{\left(g\right)}<mspace\; width="1em"></mspace>+<mspace\; width="1em"></mspace>e^{-}<mspace\; width="1em"></mspace>\to <mspace\; width="1em"></mspace>H_{\left(g\right)}^{-}$

4. $O_{\left(g\right)}^{-}<mspace\; width="1em"></mspace>+<mspace\; width="1em"></mspace>e^{-}<mspace\; width="1em"></mspace>\to <mspace\; width="1em"></mspace>O_{\left(g\right)}^{2-}$