I believe its true, i'm not entirely sure.
The great rift valley was formed by violent subterranean forces that tore apart the earth's crust. These forces caused huge chunks of the crust to sink between parallel fault lines and force up molten rock in volcanic eruptions.
The property that distinguishes the thermosphere most is the presence of C. Heat
The answer is A. Appalachian Mountains
When American colonists headed west they crossed what will known today as the Appalachian Mountains.
Hopes this Helps u ;)
