Explanation:

Maharashtra

The parent material for most of the black soil are the volcanic rocks that were formed in the Deccan Plateau (Deccan and the Rajmahal trap).
In Tamil Nadu, gneisses and schists form the parent material. The former are sufficiently deep while the later are generally shallow.
These are the region of high temperature and low rainfall. It is, therefore, a soil group typical to the dry and hot regions of the Peninsula.