Why this Question) Important Static geography concept from NCERT class XI. 

Ans) b 

Exp) Option b is correct.  

Black soil in India is formed by the weathering of fissure volcanic rock.  

Climatic condition along with the parent rock material is the important factors for the formation of black soil. Black soils are spread mostly across interior Gujarat, Maharashtra, Karnataka, and Madhya Pradesh on the Deccan lava plateau and the Malwa Plateau, where there is both moderate rainfall and underlying basaltic rock. 

Source:  https://ncert.nic.in/textbook/pdf/jess101.pdf  

https://www.britannica.com/place/India/Black-soils 

Subject) Geography