The correct option is C Pb2+ compounds act as oxidizing agents
Pb shows mainly +2 oxidation state frequently as compared to +4 oxidation state. This is due to the inert pair effect. Inert pair effect may be defined as inertness of inner ns sub-shell towards chemical reaction. It is seen in group 3A and 4A group especially (5s and 6s electrons).
Carbon and silicon mostly show +4 oxidation state. Tin forms compounds in both oxidation states.
So as we move down the group, due to inert pair effect lower oxidation state become more stable.
Stability of +2 oxidation state,
Ge2+<Sn2+<Pb2+
Due to higher stability of Pb2+, Pb4+ will readily undergo reduction to form Pb2+. Thus, Pb4+ act as a strong oxidising agent.