The primary result of the U.S.-Mexican War (1846-1848) was that it resulted in the United States acquiring a large portion of land known as the Mexican Cession. This territory included present-day California, Arizona, New Mexico, Nevada, Utah, and parts of Colorado and Wyoming.
So, to summarize the options you provided, the most accurate result is:
- It gave the United States territory known as the Mexican Cession.
While the war did have other implications, like fostering a sense of nationalism and raising questions about slavery's expansion into newly acquired territories, the acquisition of land was the most significant and direct outcome of the conflict.