①CH3COONa = CH3COO- + Na+（完全）,CH3COO- + H2O = CH3COOH + OH-（可逆）,溶液显碱性.
②NaHSO4 = Na+ + H+ + SO42-,溶液显酸性.
③NaCl = Na+ + Cl-,溶液显中性.
④C6H5ONa = C6H5O- + Na+,C6H5O- + H2O = C6H5OH + OH-（可逆）,溶液显碱性.
由于酸性：CH3COOH > C6H5OH,所以C6H5O-的水解程度比CH3COO-大,相同浓度时,C6H5ONa溶液的碱性更强.
所以按pH由大到小排列应该为：A ④①③②