The following solutions were prepared by dissolving \(10\, \mathrm{~g}\) of glucose \(\left(\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}\right)\) in \(250 \,\mathrm{ml}\) of water \(\left(\mathrm{P}_{1}\right)\), \(10\, \mathrm{~g}\) of urea \(\left(\mathrm{CH}_{4} \mathrm{~N}_{2} \mathrm{O}\right)\) in \(250\, \mathrm{ml}\) of water \(\left(\mathrm{P}_{2}\right)\) and \(10\, \mathrm{~g}\) of sucrose \(\left(\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}\right)\) in \(250\, \mathrm{ml}\) of water \(\left(\mathrm{P}_{3}\right)\). The right option for the decreasing order of osmotic pressure of these solutions is :

1. A \(\mathrm{P}_{2}>\mathrm{P}_{1}>\mathrm{P}_{3}\)
2. B \(\mathrm{P}_{1}>\mathrm{P}_{2}>\mathrm{P}_{3}\)
3. C \(\mathrm{P}_{2}>\mathrm{P}_{3}>\mathrm{P}_{1}\)
4. D \(\mathrm{P}_{3}>\mathrm{P}_{1}>\mathrm{P}_{2}\)