Answer
See the answer below.
Work Step by Step
a) $NH_4^+$ produces an acidic solution, $CO_3^{2-}, S^{2-}$ produce basic solutions.
b) $Br^-, ClO_4^-$ won't affect pH
c) $S^{2-}$ is the strongest base because it has a higher Kb.
d)
$CO_3^{2-}+H_2O\leftrightarrow HCO_3^-+OH^-$
$S^{2-}+H_2O\leftrightarrow HS^-+OH^-$
