Which statement best explains the concept of "manifest destiny?"

I am assuming you left off a list of statements or choices. Thus, I will share with you what Manifest Destiny meant for our country.

The people of the United States began to believe we should expand from the Atlantic Ocean to the Pacific Ocean. By 1803, we had expanded as war west as the Rocky Mountains. We expanded as far north as Canada. We controlled the lands in the South to the border with Spanish Florida. After the Louisiana Purchase, we had doubled the size of our country. People began to believe it was our duty to expand to the Pacific Ocean.

As we moved into the mid-1800s, we wanted to expand to the Pacific Ocean. We decided to annex Texas in 1845. We would have done so sooner, but there was concern about adding another slave state. We expanded into the Oregon Territory and got half of that land when we signed an agreement with Great Britain. Both the United States and Great Britain controlled the Oregon Territory. This agreement gave us the southern part of this area while Great Britain got the northern part of the area. Today, the area we got is known as the Pacific Northwest. We also wanted to get control over what is now the southwest part of our country. We went to war with Mexico over a boundary dispute regarding the Texas border. As a result of the war, we got control of the area that makes up the southwest part of the United States. We got California, Utah, Nevada, and parts of Arizona, New Mexico, Colorado, and Wyoming. We also resolved the dispute over the border between Texas and Mexico. In 1853, we made the Gadsden Purchase with Mexico giving us a strip of land in southern New Mexico and southern Arizona. We paid $10 million for the purchase of this strip of land.

Thus, by 1853, we had completed the goal of Manifest Destiny. We had spread from the Atlantic Ocean to the Pacific Ocean.