Explanation

Equivalent weight equals molecular weight divided by the valency (n-factor). For NaCl the n-factor is 1 (one Na⁺/Cl⁻ exchanged), so its equivalent weight equals its molecular weight. H₂SO₄, CaCl₂ and Na₂SO₄ all have n-factor 2, so their equivalent weights are half their molecular weights. The answer is D.