. Tyndall effect is shown by
Tyndall effect: Tyndall effect or Tyndall phenomenon is the phenomenon in which the particles suspended in the solution scatter the beam of light that is directed towards them.
Tyndall effect is a characteristic property of colloidal solution in which the particles of colloid do not allow the beam of light to pass through completely. The beam collides and scatters.
Sol is the only colloidal solution amongst the given options.
Sol is made up of solid particles suspended in a continuous liquid medium. It is a colloid of solid and liquid and hence will be the only option that shows tyndall effect.
Final Answer: The correct option is B: sol