The equation C will form a precipitate in the form of calcium carbonate.
This is the formation of an insoluble compound during a chemical reaction.
Ca(NO₃)₂(aq) + K₂CO₃(aq) → CaCO₃(s) + 2KNO₃(l)
The precipitate formed in this chemical reaction is CaCO₃ which is insoluble in water thereby making it the most appropriate choice.
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