Ionic Equilibrum

\(K_a\) values for acids \(\mathrm{H}_2 \mathrm{SO}_3, \mathrm{HNO}_2, \mathrm{CH}_3 \mathrm{COOH}\) and \(\mathrm{HCN}\) are respectively \(13 \times 10^{-2}, 4 \times 10^{-4}, 1.8 \times 10^{-5}\) and \(4 \times 10^{-10}\), which of the above acids produces stronger conjugate base in aqueous solution?