Which of the following will show “Tyndall effect”?

Tyndall effect is the phenomenon in which the path of the light beam becomes visible when a light beam enters a colloidal solution. The path becomes visible due to the scattering of light by the colloidal particles. Soap solution is an example of a colloidal solution and hence shows Tyndall effect. Salt solution, sugar solution and copper sulphate are examples of true solutions and do not show Tyndall effect.