Most products assembled in maquiladoras are __

Sold to the United States

Explanation:

The maquiladoras is a company that allows the factories to be duty and tariff-free, as the factories take the raw material and then processes them for manufacturing and exports and thus, these factories are represented in Latin America and they include central America and Mexico which resulted in a rapid industrialization program.   As the maquiladora overtook the tourism sector which is seen as a large source of the foreign exchange and wit the intro of the NAFTA the trade became more efficient with Mexico as they were cheap to use.

Themes; subfields is the answer