Read the Mexican government’s Bustamante Decree of April 1830.

Article 9. The introduction of foreigners across the northern frontier is prohibited under any pretext whatsoever, unless the said foreigners are provided with a passport issued by the agent of the republic at the point whence the said foreigners set out.

Article 10. No change shall be made with respect to the slaves now in the states, but the Federal government and the government of each state shall most strictly enforce the colonization laws, and prevent the further introduction of slaves.

What was the main reason the Bustamante Decree changed the minds of people who wanted Texas to become part of the United States?

It complicated the balance of potential slave and free states in the United States.
It showed that Mexico was prepared to defend its land against foreigners.
It showed that Mexico was eager to take immigrants from the United States.
It was a declaration of war since Mexico was trying to regulate US citizens.