The Tyndall effect refers to the scattering of light by particles in a colloid or suspension, resulting in the path of the light being visible. This effect is observed when the particles in the mixture are larger than the wavelengths of visible light. The correct answer in this case is option 2, lime juice.

Option 1, chalk powder freshly mixed with water, will show the Tyndall effect because the chalk particles are larger than the wavelengths of visible light and will scatter the light, making the path of the light visible.

Option 3, few drops of milk mixed with water, will also show the Tyndall effect because the proteins and fat globules in the milk are larger than the wavelengths of visible light and will scatter the light.

Option 4, starch solution, will show the Tyndall effect because the starch particles are larger than the wavelengths of visible light and will scatter the light.

However, option 2, lime juice, will NOT show the Tyndall effect because the particles in the lime juice are much smaller than the wavelengths of visible light. Therefore, the light will pass through the lime juice without being scattered, and the path of the light will not be visible.