Answer: A - Began the Mexican war.
Mexico resented the annexation of Texas and consequently began the Mexican war when Texas was admitted to the union. The Mexican war was an armed conflict between the Mexican and the American country. This war was fought in the year 1846-1848. The Republic of Texas was still considered as the Northern province for the Mexicans even though it had succeeded in breaking away from Mexico a decade earlier. In 1845 Texas was annexed by America this was the main reason for the Mexican war.
