The volume of a colloidal particle (Vc) as compared to the volume of a solute particle (Vs) in a true solution could be:

For a true solution, the diameter ranges from 1 to 10 angstroms. For a colloidal solution, the diameter ranges from 10 to 1000 angstroms. The volume is proportional to the cube of the diameter. Therefore, the ratio of the volumes will be approximately (1000/10)³ = 100³ = 10⁶. The closest option is Vc/Vs ≈ 10³ although it is an underestimate.