$O_2^{2-}$ is the symbol of _________ ion.

$\begin{array}{1 1}(a)\;\text{Oxide}\\(b)\;\text{Super}\\(c)\;\text{Peroxide}\\(d)\;\text{Monoxide}\end{array}$

$O_2^{2-}$ is the symbol of peroxide ion.
Hence (c) is the correct answer.