Arrange the following solution in the increasing order of their osmotic pressure (a) 34.2 g/litre sucrose (b) 60 g/litre urea ($NH_2CONH_2$) (c) 90 g/litre glucose (d) 58.5 g/litre sodium chloride. Give reason in support of your answer

Sucrose < Glucose < Urea < NaCl
Hence (A) is the correct answer.