What Is the Balanced Reduction Half-Reaction for the Reaction

Multiple Choice

What is the balanced reduction half-reaction for the reaction
3Mg(s) + N₂(g) → Mg₃N₂(s)

A) Mg²⁺ + 2e− → Mg
B) Mg → Mg²⁺ + 2e−
C) Mg²⁺ → Mg + 2e−
D) N₂ + 6e− → 2N³⁻
E) N₂ → 2N³⁻+ 6e−