Regular use of which of the following fertilizers increases the acidity of soil?

Ammonium sulphate $({\text{NH}}_4{)}_2{\text{SO}}_4$ is a salt of a weak base $({\text{NH}}_4\text{OH})$ and a strong acid $({\text{H}}_2{\text{SO}}_4)$.In the soil, it undergoes hydrolysis:
$$({\text{NH}}_4{)}_2{\text{SO}}_4\to 2{\text{NH}}_4^{+}+{\text{SO}}_4^{2-}$$
$${\text{NH}}_4^{+}+{\text{H}}_2\text{O}\rightleftharpoons {\text{NH}}_4\text{OH}+{\text{H}}^{+}$$
The release of ${\text{H}}^{+}$ ions increases the concentration of hydronium ions in the soil, thereby increasing its acidity.