Answer : 4. "Black cotton soils "
Explanation :

1. Indian black soil is commonly known as black cotton soil or "Regur".

2. Black soil is known as black cotton soil because cotton is an important crop which is grown in this type of soil.

3..Black soil is good for the production of cotton, oilseeds, wheat, linseed, millet and tobacco. This soil is rich in calcium carbonate, potash, lime but has low phosphorus content. Black soils can hold a lot of moisture.

4. It is mostly found in the peninsular plateau of India.