How many million acres did the US acquire from Texas in 1845?

The correct answer is based on historical context regarding the annexation of Texas into the United States in 1845. At that time, the Republic of Texas encompassed a significant portion of land, which is equivalent to approximately 79 million acres. This acquisition was a bold expansion of U.S. territory, fulfilling the idea of Manifest Destiny, which was prevalent during that era. The annexation was a contentious issue, influencing U.S. politics and contributing to the Mexican-American War that followed.

Understanding this specific figure is crucial for grasping the scale of land acquisition during the period as it set the stage for further westward expansion and the eventual establishment of state boundaries in the southwest region. The other options suggest figures that do not align with the historical records of the Texas land area, illustrating how the land's dimensions have been vital in shaping U.S. geography and policy decisions.