The Formation of Vegetable Mould Through the Action of Worms is the title of a classic study by Charles Darwin.What is the true role of earthworms in soil formation?

A)Earthworms can ingest their weight in soil every day,enriching it with organic material.
B)Earthworms consume valuable air that is needed by plant roots.
C)Earthworms are harmful to plant and spread plants root diseases.
D)All of the choices are correct.
E)None of the choices is correct.