The unifying theory that explains such diverse subjects as continental growth, volcanic eruptions, and creation of mountain ranges is known as:

Plate tectonic theory is the universally accepted theory that describes the processes of mountain building, sea floor spreading, volcanic eruption as well as the growth of continents.

This theory explains how two plates moves and what are the structures associated with this.

Plate tectonic movement is of three types-

river is shown in this type of map

because the center-south is called the heart of the country