Pheretima posthuma (earthworm) is highly useful as or Most important use of earthworm is

Options

A. Their burrows make the soil loose
B. They make the soil porous, leave their castings and take organic debris in the soil
C. They are used as fish meal
D. They kill the birds due to biomagnification of chlorinated hydrocarbons

Answer

B

Explanation

Earthworm lives in burrows made by burrowing and swallowing the soil thus make the soil porous.