Which of the Following Ammonium Salts Would Be Considered an Acidic

Multiple Choice

Which of the following ammonium salts would be considered an acidic salt when dissolved in water?
I. (NH₄) (CH₃COO) K _a(CH₃COOH) = 1.8×10 ^{- 5} K _b(NH₃) = 1.8×10 ^{- 5}
II. NH₄CN K _a(HCN) = 6.2×10 ^{- 10} K _b(NH₃) = 1.8×10 ^{- 5}
III. NH₄Cl

A) All ammonium salts are acidic
B) All ammonium salts are basic
C) III only
D) I and II
E) II and III