Correct Answer: Phosphorus

Solution : The correct answer is Phosphorus .

The black soil is also known as regur or black cotton soil. The soil is clayey and rich in lime, iron, magnesium, calcium carbonate and potash but it lacks phosphorus, nitrogen and organic matter. The soil can retain moisture for a long period which helps the crop to grow during the hot season. They generate cracks during the dry season and become sticky during the wet.