What is the function of silkworm?

The silkworm is the larva or caterpillar of a silk moth. It is an economically important insect, being a primary producer of silk. A silkworm's preferred food are white mulberry leaves, though they may eat other mulberry species and even the osage orange. The moth is important because it makes silk. It is entirely dependent on humans, and it no longer lives in the wild. Silkworms eat mulberry leaves, and are native to northern China.

The light is great source of energy

The answer is letter c