The correct option is B nalla
Some agricultural lands in Dokur are covered by shallow black soil. This type of soil is also called nalla. The soil cover typically has a depth of about 60 cm. Below this shallow soil, one may find a layer of hard rock. Regadi, on the other hand, is another name for deep black soil. Choudu and garusu are two other types of soil that are full of pebbles and very infertile.