Why are earthworm called the friends of the farmers ?

why earthworm is called the friend of farmer ?

Why are earthworms called as farmer's friends?

Why is an earthworm called detritivore?

Assertion: The earthworms are referred to as the farmer's friend. Reason : Earthworm help in the breakdown of complex organic matter as well as in loosening of the soil.

Why is earthworm called nature's ploughman?