Which of the following earthworm species is frequently used for vermicomposting?

All of these 

The correct answer is Option (4) – All of these
Vermicompost is composed of the organic waste transformed through different earthworm species' digestive systems into a homogeneous product of high nutritional value and with great possibilities for its application in agriculture. This process allows the stabilization of solid residues, showing great possibilities when the concentration in cellulose fibers is high.

In this case, different species of earthworms are used, although the most frequently used species are Eisenia foetida, Eudrilus eugeniae, and Perionyx excavatus.

One of the main advantages of the use of earthworms in the production of compost is the production of a higher concentration of nutrients through the biological activity of these worms, which might be compared to traditional composting and allow the reuse of residues of low fertilization potential .