Which of the following statements is correct for oleum?

What are the values of electron gain enthalpy in groups $16$ and $17$? How do they change?

Red hot iron absorbs $SO_2$ giving the product

The nature of oxide $(TeO_2)$ and hydride $(TeH_2)$ formed by $Te$ respectively are $:$

Which of the following ions does not have $S-S$ linkage?

Which of the following statements is correct regarding the oxygen family (Group $16$)?
$(i)$ The stability of $+6$ oxidation state decreases down the group and the stability of $+4$ oxidation state increases down the group.
$(ii)$ The stability of $+6$ oxidation state increases down the group and the stability of $+4$ oxidation state decreases down the group.
$(iii)$ Bonding in $+4$ and $+6$ oxidation states is primarily covalent.