D) All three bulbs would go out because the circuit would no longer have a ground thereby deeming it "open".
According to provided equation it is clear that Zn metal is oxidized from Zn⁰ into Zn²⁺ which means that Zn metal dissolves and forming Zn²⁺ solution so the correct answer is:
mass of the Zn(s) electrode decreases
