Ag can be used to remove lead from lead (II) nitrate.
Option C
Explanation:
In order to separate the lead from lead (II) nitrate, we have to react it with another solution having same oxidation state and which can replace lead and make it as a precipitate.
So among the given options, Ag has high tendency to react with nitrate easily. Since, the oxidation state of Ag is also similar to the oxidation state of Pb, it can easily substitute Pb. Thus, Ag can be used to remove lead from lead nitrate.
