Explanation

(d)
(A)$CH_{3}COONH_{4} + H_{2}O \longrightarrow CH_{3}COOH + NH_{4}OH$
Ammonium acetate
Although both ($CH_{3}COOH\ and\ NH_{4}OH)$ of them are weak still $CH_{3}COOH$ is slightly more acidic.
$\therefore$ Solution is acidic in nature.
(B)$NH_{4}Cl\ \ \ \ \ \ + H_{2}O\ \ \longrightarrow NH_{4}OH\ \ + HCl$
ammonium chloride weak base strong acid
$\therefore$ Solution is acidic in nature.
(C ) $\left( NH_{4} \right)_{2}SO_{4}\ \ \ + H_{2}O \longrightarrow 2NH_{4}OH\ \ \ + H_{2}SO_{4}$
ammonium sulphate weak base strong base
$\therefore$ Solution is acidic in nature.
(D)$CH_{3}COONa\ \ \ \ + H_{2}O\ \ \longrightarrow CH_{3}COOH\ \ \ \ + NaOH$
sodium acetate weak acid strong base
$\therefore$ Solution is basic in nature.