Vermicomposting is a method of composting that involves

Vermicomposting uses earthworms to break organic waste into nutrient-rich castings.

Silkworms produce silk and have no role in composting.

Bacteria assist decay but do not define the vermicomposting method.

The claim that none applies is wrong because earthworms are essential to it.

Species such as Eisenia fetida are commonly used for the purpose.

The worm castings, or vermicompost, improve soil structure and fertility.