In the equation below, which species acts as the oxidizing agent?

$\mathrm{Pb}\left(s\right)+{\mathrm{PbO}}_2\left(s\right)+2{\mathrm{H}}^{+}\left(aq\right)+2{\mathrm{HSO}}_4^{-}\left(aq\right)$ $⟶2{\mathrm{PbSO}}_4\left(s\right)+2{\mathrm{H}}_2\mathrm{O}\left(l\right)$

In the equation below, ${\mathrm{PbO}}_2\left(s\right)$ species acts as the oxidizing agent.

$\mathrm{Pb}\left(s\right)+{\mathrm{PbO}}_2\left(s\right)+2{\mathrm{H}}^{+}\left(aq\right)+2{\mathrm{HSO}}_4^{-}\left(aq\right)$$⟶2{\mathrm{PbSO}}_4\left(s\right)+2{\mathrm{H}}_2\mathrm{O}\left(l\right)$

$\mathrm{Pb}$ is oxidized, ad ${\mathrm{PbO}}_2$ is reduced.
${\mathrm{PbO}}_2$ is oxidizing agent and $\mathrm{Pb}$ is reducing agent.

Hence, option B is correct.