Sun is a natural  and not man-made source of light. It is the primary source of light for our planet. This is the correct option.

Planets are not luminous objects. They do not give light energy of their own. Thus, this is the correct option.

The glow worm is a medium to large sized invertebrate that is famous for having a green and yellow coloured light on the end of it's tail. This is the correct option.

This is the correct option. Wood is not an optical medium. Light energy cannot pass through wood.

Smoke is the correct option, as it is a heterogeneous medium. An optical medium which has different compositions at different points is called a heterogeneous medium.

This is the correct option. Tissue paper is not an opaque body. It is a translucent body. It partially allows the light energy to pass through it.

This is the correct option. The path along which light energy travels in a given direction is called ray of light.

This is the correct option. Glass is a homogenous mixture. It has a uniform composition.

This is the correct option, as this is not a condition for the formation of a shadow. There must be an opaque body to obstruct the light, and not a transparent body to pass the light.

Oiled paper is a translucent medium, i.e.  it allows the light to partially pass through it. This is the correct option.

This is not a characteristic of a shadow. Objects of different colours, but of same shape form same kind of shadow, and not different shadows.

A solar eclipse is a type of eclipse that occurs when the moon passes between the sun and earth, and the moon fully or partially blocks the sun. Thus, this is the correct option.

This is the correct option. The speed of light is not 300,000 m/s, but it is 300,000 km/s. The light from the sun reaches the earth in 8.33 minutes.

This is the correct option. This is not a characteristic of the image in a pinhole camera. The images are not enlarged, but are diminished, i.e.  they are very small as compared to the size of the objects.

Image in a pinhole camera can be smaller or bigger than the opaque body, is a false statement. Image in a pinhole camera is always smaller than the object. It is not smaller or bigger than the image.