There were many causes of the war, but the biggest reasons were Mexico's lingering resentment over the loss of Texas and the Americans' desire for Mexico's western lands, such as California and New Mexico. The Americans believed their nation should extend to the Pacific: this belief was called "Manifest Destiny
I'm not exactly sure what the question is but I'm going to say that the answer is: <span>A. Roman culture influenced the development of Western Civilization.