President James K. Polk campaigned on a platform of westward expansion. How much did he live up to that promise during his presidency?

A. The United States grew by about a third.

B. The United States lost territory.

C. The United States added a small amount of territory.

D. The United States remained about the same.

James Knox Polk, the eleventh President of United States advocated the annexation of Oregon and Texas. He got the approval from the congress when Mexican troops killed 16 US soldiers during the aggression led by U. S. General Zachary Taylor across the disputed area to the banks of the Rio Grande in 1846 By using a combination of military threats and diplomacy, Polk managed to arrive at a compromise with England that set the 49th parallel as the Oregon Territory's northern boundary and expanded through the west

A

Explanation:

The United States grew under the direction of James Knox Polk, the 11th president. throughout his mandate as president, the United States annexed Texas, The Oregon Territory, and gained significant areas due to Mexico's defeat in the Mexican American war, this area being known as the Mexican Cession which included the present day states of California, Nevada, and Arizona amongst many others.