Which of the following  has the least  tendency to act like oxidant

Stability of

$\begin{array}{l}{\mathrm{Bi}}^{+5}<{\mathrm{Bi}}^{+3}\\ {\mathrm{Pb}}^{+4}<{\mathrm{Pb}}^{+2}\end{array}$

${\mathrm{Tl}}^{+3}<{\mathrm{Tl}}^{+}$due to inert pair effect.

$\therefore {\mathrm{Tl}}^{+3},{\mathrm{Pb}}^{+4},{\mathrm{Bi}}^{+5}$are good oxidants

Stability of ${\mathrm{Sn}}^{+4}>{\mathrm{Sn}}^{+2}$

$\therefore {\mathrm{Sn}}^{+4}$cannot act like oxidant