Indigenous cultures possess unique knowledge of the medicinal uses of animals. According to a 2021 study,

Choice C is the best answer because it most logically completes the text’s discussion of the relationship between Indigenous languages and knowledge of the medicinal uses of animals. The text states that Indigenous cultures possess special knowledge of the medicinal uses of animals, which is reflected in their vocabulary. The text then discusses how tribal nations are working to preserve their languages, whose daily use is declining as globally dominant languages become increasingly dominant in Indigenous communities. Given that the languages of tribal nations in what is now the United States function as repositories of knowledge about animals’ medicinal uses, it logically follows that continued use of those languages will assist with passing on knowledge about the medicinal value of animals native to the tribal nations’ lands.

Choice A is incorrect because the text states that preserving Indigenous languages will increase the knowledge, not the number, of medicinal animals. Choice B is incorrect because the text is concerned with how vocabulary about the medicinal value of animals can be preserved through the continued daily use of Indigenous languages, not with how such vocabulary can be incorporated into globally dominant, non-Indigenous languages. Moreover, the text explains that the exclusive use of globally dominant languages in Indigenous communities comes at an expense to the continued daily use of those communities’ languages. Given this relationship, it is unlikely globally dominant languages would borrow Indigenous vocabulary pertaining to  animals’ medicinal uses. Choice D is incorrect because the text doesn’t discuss physical access to medicinal animals, instead focusing on Indigenous knowledge and language surrounding the medicinal uses of animals.