A normal salt is formed when all of the acidic hydrogen in an acid is replaced by a metal ion or ammonium ion.
Among the given compounds, only Na2CO3 (sodium carbonate) is a normal salt because it is derived from a strong base (NaOH) and a weak acid (H2CO3), and all of the acidic hydrogens of H2CO3 have been replaced by Na+.
NaHS (sodium hydrosulfide), NaHSO4 (sodium hydrogen sulfate), and NaHCO3 (sodium bicarbonate) are not normal salts. NaHS and NaHSO4 are acidic salts because they still have some acidic hydrogen atoms remaining. NaHCO3 is a basic salt because it still has some basic hydroxide ions.