When laying underground iron pipes, the pipe is usually connected to a metal
plate by a wire. The corrosive environment of the soil preferentially oxidizes the
metal plate instead of the iron pipe. The metal plate gradually corrodes away
preventing the iron pipe from rusting.
The diagram shows the placement of the underground pipe and the metal plate.
Five metal plate options are shown as well as the activity series of metals.

Based on the activity series of metals shown, which set of metal plates may
prevent the iron pipe from corroding?
A. Pb, Cu
B. Mg, Cu
C. Zn, Pb, Cu
D. Zn, Al, Mg