Calcium carbonate is the salt among the given options.
Calcium carbonate ( CaCO3) can be regarded as which appears as white and odorless powder or as a colorless crystals it is insoluble in water.
The chemical formula is CaCO3. It can be used as an antacid as well as food colouring and a food firming agent and a fertilizer.
Calcium carbonate is calcium salt as well as carbonate salt with one-carbon compound
Salt can be regarded as substance which is produced by reaction between acid and base. It consists negative ion (anion) of that acid as well as positive ion(cation) of the base.
Sodium hydroxide is a base and not a salt
Carbonic acid is an acid and not a salt
Therefore, calcium carbonate is the only salt in the among the given options.
