Final answer:
The support for the United States' acquisition of territories was largely based on the need for American industries to find new sources of raw materials and markets overseas, which was a key economic argument for imperialist expansion during the late nineteenth century. Therefore, the correct option is D.
Step-by-step explanation:
One argument that was used in support of the United States' acquisition of territories was the need for American industries to secure raw materials and new markets overseas (Choice D). This economic rationale underpinned much of the late-nineteenth-century imperialist expansion. The growth of American industries during this period fueled the demand for new resources and markets beyond the domestic frontiers, thereby leading to overseas acquisitions and justifying these actions with the pursuit of national economic interests.
For instance, after the annexation of Hawaii, and later with the control over islands like Guam, the Philippines, and Puerto Rico, the United States gained strategic positions for military and commercial purposes. Furthermore, American Imperialism was driven by the ideology of 'American exceptionalism,' which claimed that the nation had a unique mission to spread democracy and liberty globally.
During the expansions, questions arose about the compatibility of such imperialist actions with American democratic principles, with critics such as William Jennings Bryan arguing that it ran counter to the nation's constitutional and legal framework. Yet, the strategic and economic benefits provided by these newly acquired territories were also part of the imperialist agenda.