Final answer:
Patagonia is the sparsely populated Grassland desert region at the southern end of South America shared by Argentina and Chile, known for its prairie grasslands, and semiarid climate due to the rain shadow effect.
Step-by-step explanation:
The sparsely populated Grassland desert region at the southern end of South America is known as Patagonia. This region is shared by Argentina and Chile and is characterized by its vast prairie grasslands with a semiarid climate, which is largely a result of the rain shadow effect caused by the Andes mountains to the west.
Main economic activities here include raising cattle and other livestock, and in recent times, there has been a growing interest in natural resources such as oil, natural gas, and valuable minerals.
The Patagonia region extends into areas with tundra-like conditions and includes the treeless plains of Tierra del Fuego and rugged Southern Andes. Interestingly, Patagonia is also seeing afforestation efforts, particularly with pines in Argentina. Despite these developments, the region remains thinly populated.