For the first question about the causes of the Mexican-American War, the correct answer is:
C. The United States annexed Texas.
The annexation of Texas by the United States in 1845 was a significant factor that led to tensions between the U.S. and Mexico, eventually triggering the war.
For the second question about the results of the Mexican-American War, the correct answer is:
C. It gave the United States territory known as the Mexican Cession.
The Mexican Cession included present-day California, Nevada, Utah, Arizona, and parts of Colorado and New Mexico, and it was a direct result of the war.