`PbO_(2)` is a stronger oxidising agent than `SnO_(2)`.
Or `PbO_(2)` can act an oxidiside agent.

Answer

In `PbO_(2)` and `SnO_(2)` both lead and tin present in `+4` oxidation state.But due to stronger inert pair effect,`Pb^(2+)` ion is more stable than `Sn^(2+)` ion. In other words, `Pb^(4+)` ions i.e. `PbO_(2)`, is more easily reduced to `Pb^(2+)` ions than `Sn^(4+)` ions are reduced to `Sn^(2+)` ions.Thus, `PbO_(2)` acts as a stronger oxidising agent than `SnO_(2)`.