Which of the following has only $\mathrm{\sigma }$ bonds?

${\left[{\mathrm{XeOF}}_3\right]}^{-}$is ${\mathrm{sp}}^3$ hybridized. ${\mathrm{sp}}^3$ hybridized because there is 4 regions of electron density. Three doubly-bonded $\mathrm{O}$ atoms to$\mathrm{Xe}$, and one lone pairs on the central $\mathrm{Xe}$ atom. For ${\mathrm{sp}}^2$ hybridization, there needs to be three regions of electron densities and do not contain any π bonds. They contain only σ bonds.
Hence, the correct option is A.