Explain what it means to divide Middle America into a Euro-Amerindian Mainland and a Euro-African Rimland.

The rimland was easily accessible to European ships, and the mainland was more isolated from European activity.

Explanation:

America has various types of landscapes, regional approach to the geography of a realm aids us to compare and contrast a place’s features and characteristics. Location and the physical differences gives the division of Middle America into two geographical areas according to occupational activities and colonial dynamics: the rimland, which includes the Caribbean islands and the Caribbean coastal areas of Central America, and the mainland, which includes the interior of Mexico and Central America.

Colonialism waxed greater in the "Rimland" because it composes mainly of islands and coastal areas that were easily accessible to European ships. Ships could easily sail into a bay to make port and claim the island for their home country. After an island or coastal area was claimed, the areas was transformed of through plantation agriculture.

The "Mainland", which includes the interior of Mexico and Central America.

yup! you are correct it is b.