Final answer:
The Manifest Destiny supported the annexation of Texas from an American point of view, as it was seen as a divine right and part of the nation's mission to expand its territory. The correct answer is d. The Manifest Destiny.
Step-by-step explanation:
From an American point of view, the reason that supported annexation of Texas was d. The Manifest Destiny. Manifest Destiny was the belief that American expansion was not only inevitable but divinely ordained and just.
It was viewed as a mission and purpose for the United States to expand its territory.
This belief was a powerful motivator for the annexation of Texas, as it aligned with the vision of an expanding American empire.
In contrast, Texas having slavery (a), having debt (b), and conflict with Mexico (c) were seen as obstacles or considerations rather than supporting reasons for annexation. The annexation of Texas was fueled by the desire for westward expansion.