Free trade has led to move more manufacturing jobs in Mexico because it?

1) They encourage them to work harder
2)they make it possible for more people to become U.S. citizens
3)they discourage them from working for reform
4) they increase their dependence on the U.S. economy

I think #4 THANK YOU FOR YOUR HELP

2 answers

What or who is "they" in your answer choices?
Jobs, sorry for the confusion.