What situation or event initially escalated the conflict between the Mexican government and American settlers?

an argument over a cannon in the town of Gonzales

the Mexican government's
insistence that colonists speak Spanish

American settlers' rejection of the provisions of the Mexican immigration policy

turmoil in the Mexican government after receiving independence from Spain

The correct option is:

American settlers' rejection of the provisions of the Mexican immigration policy

Explanation:

After Mexico gained independence from Spain, they allowed the American settlers to immigrate and occupy the northern area, which was previously occupied by native American Tribes. Mexican government also aided them by suspending tariffs and taxes for them. However, Americans poured into the area in following years, such that Mexican got outnumbered by Americans. Mexican government was afraid that USA might take control over the area because of a large population of American settlers. To stop that, Mexican government stopped any further immigration in 1830 and also reinstated all the taxes and tariff. This escalated the conflict between American settlers and Mexican government.