The streaming of light beams coming from the Sun through trees is said to have suggested that light travels in straight line. The particles on the path of light beams are visible to us because

The phenomenon described is a classic example of the Tyndall Effect. When sunlight passes through a dense canopy of trees, it interacts with tiny particles suspended in the air, such as dust, smoke, and moisture droplets.

Option B is correct because these particles scatter the light. Scattering occurs when light rays strike small particles and are redirected in various directions. When this scattered light reaches our eyes, the path of the light beam becomes visible to us, making the particles themselves appear to glow.

• Scattering: The redirection of light by small particles in all directions.
• Reflection: Usually refers to light bouncing off a smooth surface at a specific angle.
• Refraction: The bending of light as it passes from one medium to another.

According to NCERT Science textbooks, the visibility of a light beam in a colloidal solution or air is due to the scattering of light by particles.