Which molecules represented by the bold atoms are in their highest oxidation state?

• A

  ${\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_8$

• B

  ${\mathrm{P}}_4{\mathrm{O}}_{10}$

• C

  ${\mathrm{F}}_2\mathrm{O}$

• D

  ${\mathrm{Mn}}_2{\mathrm{O}}_7$