Among the following , the one which can act as both as Bronsted acid as well as Bronsted base is

Among the following , the one which can act as both as Bronsted acid a

1.	Among the following , the one which can act as both as Bronsted acid as well as Bronsted base is
Answer» `H_(3)PO_(4)` `AlCl_(3)` `CH_(3)CO O^(-)` `H_(2)O` ANSWER :D