What Is the Oxidizing Agent in the Reaction 2 NO₂(g) $\rightarrow$

What is the oxidizing agent in the reaction 2 NO₂(g) + O₃g) $\rightarrow$ N₂O₅(s) +O₂ (g) ?

A) NO₂
B) O₃
C) N₂O₅
D) O₂
E) This is not a redox reaction.