Which of the following reactions is an example of a redox reaction ?

Question

( A ) $XeF_6 + H_2O \to XeF_4 + 2$HF
( B ) $XeF_2 + PF_5 \to [XeF]^+PF_6^-$
( C ) $XeF_4 + O_2F_2 \to XeF_6 + O_2$
( D ) $XeF_6 + 2H_2O \to XeO_2F_2+4HF$