已知：O₂(g) = O₂⁺(g)+e^－          H₁=" +1175.7" kJ·mol^-1
PtF₆^－(g) =PtF₆(g)+e^－      H₂=" +771.1" kJ·mol^-1
O₂⁺(g)+PtF₆^－(g) =O₂PtF₆(S) H₃=" -482.2" kJ·mol^-1
则反应O₂(g)+PtF₆(g) = O₂PtF₆ (s)的H是（  ）

A．77.6 kJ

B．-77.6 kJ·mol^-1

C．+77.6kJ·mol^-1

D．-886.8kJ·mol^-1