Question

why did mexicans create the empresario system that eventually led to the texas revolution?
to expand the institution of enslavement into texas
to prevent the u.s. from trying to annex texas
to unite with native americans and keep u.s. settlers out of texas
to populate and economically develop settlements in texas

Explanation:

The empresario system was established by Mexico to encourage settlement in Texas. The goal was to populate the region and develop it economically. The other options are incorrect: expanding slavery was not the main goal (Mexico had restrictions on slavery), preventing U.S. annexation was not the primary motive of the empresario system (in fact, the system allowed U.S. settlers which complicated things later), and uniting with Native Americans to keep U.S. settlers out was not the purpose (the system brought in settlers, including U.S. ones).

Answer:

D. to populate and economically develop settlements in Texas