Many of the new arrivals to mexico city are underemployed, which means they are

Underemployment is a term used in economics to describe workers who have jobs that does not use the worker's skills or leaves them idle or without the full hours they need.

It means that they are illegal immigrants.

Mexico is the country that has a large border with the United States, so it has become a route of illegal immigrants from various countries trying to enter the United States.

However, the tightening of immigration laws and the dangers of illegal crossing make many of these immigrants give up and remain in Mexico itself. In desperation to survive, these immigrants who can not cross the border accept subaltern underemployment in the cities of Mexico, that is, Mexico is also a country that receives illegal immigrants.

your answer will most likely be a.

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