The correct answer is A. Mexico viewed the events as an unjustified US attack on Mexican soldiers, while the United States viewed the events as an illegal invasion of the United States by Mexico.
The Mexican-American War was precipitated by conflicts over territorial boundaries after the U.S. annexation of Texas. The U.S. President James K. Polk portrayed the conflict as a result of Mexican aggression, while Mexico saw the U.S. actions as an unwarranted invasion of its sovereign territory.