Final answer:
The region known for developing an economy dependent on cash crops, due to its fertile land and long growing season, is North America, specifically the southeastern area.The correct option is d.
Step-by-step explanation:
An economy dependent on cash crops developed in the region of North America, specifically in the southeastern portion. This area was known for its fertile land and long growing season, which were conducive to agricultural development. The northeast region along the coast also nurtured plantation agriculture during the colonial era, relying on crops such as sugarcane. However, it's crucial to note that reliance on cash crops can lead to issues such as food insecurity and economic vulnerability, especially in the case of monoculture farming systems.