List of top Chemistry Questions on Oxidation And Reduction Reactions asked in JEE Main

The number of ions from the following that are expected to behave as oxidising agent is: $\text{Sn}^{4+}, \, \text{Sn}^{2+}, \, \text{Pb}^{2+}, \, \text{Tl}^{3+}, \, \text{Pb}^{4+}, \, \text{Tl}^{+}$