Identification of ions and gases — practice question

Which ion produces a precipitate that dissolves in excess in both aqueous ammonia and aqueous sodium hydroxide?

• Acalcium ion, Ca$^{2+}$
• Bcopper(II) ion, Cu$^{2+}$
• Ciron(III) ion, Fe$^{3+}$
• Dzinc ion, Zn$^{2+}$