Which part of this map is the subregion central america

D. Subregion 4.

Explanation:

Central America is the isthmus connecting North and South America, that also comes between the Caribbean Sea and the Pacific Ocean, is connected to South America by the Isthmus of Panama. It covers from Mexico´s southern frontier to the northwest border of Colombia, including El Salvador, Nicaragua, Belize, Guatemala, Honduras, Panama, and Costa Rica. Central America is often described as a subcontinent of the Americas.  

entering that problem on the tube you may come up with an answer

b is correct

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