Dioxygenyl hexafluoroplatinate, $\mathrm{O}{}_2[\mathrm{PtF}{}_6]$, is made of the cation $\mathrm{O}{}_2{}^{+}$ and the anion $[\mathrm{PtF}{}_6]{}^{-}$ (F is $-1$). Which option gives the oxidation number of Pt and the average oxidation number of each O atom?

1. APt $+5$; O $-\frac{1}{2}$
2. BPt $+5$; O $+1$
3. CPt $+5$; O $+\frac{1}{2}$
4. DPt $+6$; O $+\frac{1}{2}$