In addition to English, Spanish is increasingly spoken in areas near the southwestern border of the United States. What type of region does this gradual change of language reflect

Functional region

Explanation:

In addition to English, Spanish is increasingly spoken in areas near the southwestern border of the United States. Functional region is the type of region that represent the gradual change of language reflect in the area near southern western border of the United state.

Functional region is an area organized to function as a single unit, based around specific activity or an area which has a primary function.borders towns can be considered functional region because highways, railroads, subways, and buses move people from the suburbs of mexico to the southwestern border, this influx movement of people leads to the increasingly uses of Spanish in that area.

a would be the answer