For the species $\mathrm{HSO}_4^{-}$and $\mathrm{NH}_3$ their conjugative acids respectively are
For the species $\mathrm{HSO}_4^{-}$and $\mathrm{NH}_3$ their conjugative acids respectively are
$\mathrm{SO}_4^2$ and $\mathrm{NH}_4^{+}$
$\mathrm{SO}_4^2$ and $\mathrm{NH}_2$
$\mathrm{H}_2 \mathrm{SO}_4$ and $\mathrm{NH}_4^{+}$
$\mathrm{H}_2 \mathrm{SO}_4$ and $\mathrm{NH}_2$
Solution
A conjugate acid, within the Bronsted Lowry acid base theory, is a chemical compound formed when an acid donates a proton $\left(\mathrm{H}^{+}\right)$to a base. In other words, it is a base with a hydrogen ion added to it, as in the reverse reaction it loses a hydrogen ion. Thus, conjugate acid of $\mathrm{HSO}_4^{-}$is $\mathrm{H}_2 \mathrm{SO}_4$ and conjugate acid of $\mathrm{NH}_3$ is $\mathrm{NH}_4^{+}$. Hence, the correct option is (3).