". . . But now, after reiterated menaces, Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon the American soil. She has proclaimed that hostilities have commenced, and that the two nations are now at war. "As war exists, and, not withstanding all our efforts to avoid it, exists by the act of Mexico herself, we are called upon by every consideration of duty and patriotism to vindicate with decision the honor, the rights, and the interests of our country. . . ." –President James K. Polk, message to Congress, May 11, 1846 Which "act of Mexico herself," referred to by President Polk in this passage, was the cause of war between the United States and Mexico?

A. Mexico’s refusal to discuss the U.S. offer to buy California and New Mexico
B. Mexico’s massacre of the Alamo defenders
C. Mexican soldiers’ attack on General Zachary Taylor’s forces in a disputed border area
D. Mexico’s refusal to honor the U.S. annexation of Texas
is it C

Yes, that was the excuse President Polk used to ask for war with Mexico.

Yes, you are correct. The "act of Mexico herself" referred to in this passage, which was the cause of war between the United States and Mexico, is C) Mexican soldiers' attack on General Zachary Taylor's forces in a disputed border area.