At same molar concentration, the osmotic pressure will depend on van't Hoff factor 'i'.
$\mathrm{\pi }=\mathrm{i}\mathrm{C}\mathrm{R}\mathrm{T}$
i.e., more the value of 'i' more will be the value of osmotic pressure.
Thus, osmotic pressure will lie in the sequence.
$\underset{\mathrm{A}{\mathrm{l}}_2(\mathrm{S}{\mathrm{O}}_4{)}_3}{{\mathrm{\pi }}_1(\mathrm{i}=5)}>\underset{{\mathrm{K}}_3\mathrm{P}{\mathrm{O}}_4}{{\mathrm{\pi }}_2(\mathrm{i}=4)}>\underset{\mathrm{B}\mathrm{a}\mathrm{C}{\mathrm{l}}_2}{{\mathrm{\pi }}_3(\mathrm{i}=3)}>\underset{\mathrm{U}\mathrm{r}\mathrm{e}\mathrm{a}}{{\mathrm{\pi }}_4(\mathrm{i}=1)}$