Costa Rica is the narrow country that curves from the west to the east in Central America. It is situated between Nicaragua to the north and Panama to the south.
Panama is a narrow country in Central America that curves from west to east. It is the southern most county in North America connecting it to South America via Colombia.
It's Panama (and it's borders are Colombia[South America], Costa Rica, Caribbean Sea, and the Pacific Ocean).
Panama
the narrow county that curves from the west to the east is Panama and its borders are Costa Rica and Colombia.
An isthmus is a narrow strip of land that connects to larger land areas. The Central American country of Panama is an isthmus that connects the southern portion of North America with the continent of South America.
A narrow strip of land such as this is called an isthmus.
You are getting North America confused with Northern America, which is a common mistake. Northern America is a subregion of the continent of North America. It includes Canada, the US, and sometimes Mexico. Central America is also a subregion of North America, sometimes mistakenly included in South America or as a separate continent. No Central American country connects South America to North(ern) America. Panama is connected to South America, but not to Northern America. Guatemala is connected to Northern America, but not to South America.
Isthmus of Panama
a toboggan
the canal was needed for America's self-defense
Central America joins North and South America. Central America is made up of these nations: Belize, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, and Panama. However, in some parts of the world Mexico is thought of as part of Central America. On the other hand, the European Union considers neither Mexico nor Belize part of Central America.