Write the complete ionic equation for the reaction below:

2NH₄Cl(aq) + Hg₂(NO₃)₂(aq) --> Hg₂Cl₂(s) + 2NH₄NO₃(aq)

a) 2NH₄⁺(aq) + 2Cl⁻(aq) + 2Hg²⁺(aq) + 2NO₃⁻(aq) → Hg₂Cl₂(s) + 2NH₄⁺(aq) + 2NO₃⁻(aq)
b) NH₄Cl(aq) + Hg₂(NO₃)₂(aq) → Hg₂Cl₂(s) + NH₄NO₃(aq)
c) NH₄⁺(aq) + Cl⁻(aq) + Hg₂²⁺(aq) + 2NO₃⁻(aq) → Hg₂Cl₂(s) + 2NH₄⁺(aq) + 2NO₃⁻(aq)
d) NH₄⁺(aq) + Cl⁻(aq) + Hg(NO₃)₂(aq) → HgCl₂(s) + NH₄NO₃(aq)