(D)

Only the dihydrogen phosphate ion is able to either donate a proton (in the presence of a base) or accept a proton (in the presence of a very strong acid). The hydroxide ion (option A) cannot donate a proton. The hydronium ion (option B) cannot accept a further proton. The acetate ion (option C) cannot donate another proton. The ammonium ion (option E) cannot accept a further proton.