Historically, the map shown is relevant because it shows
a)
the effect of the "northwest ordinance."
trails used in the relocation of native americans.
c)
how the united states completed its "manifest destiny."
d)
the migration of people out of the california territory.

The correct answer is C. Historically, the map shown is relevant because it shows how the United States completed its "Manifest Destiny".

Explanation:

Manifest Destiny refers to the political and social movement that advocated imperialism in the United States in the second half of the 19th century.  The phrase was used primarily by Democrats in the 1840s to promote annexation of the western territory of the United States: Oregon, Texas, and the Mexican cession.

The movement finds its origin in the Democratic Party but was later boarded by the Republican Party. They believed that destiny had set the United States to grow into a great power that could compete with the European empires. The belief in the superiority of the Anglo-Saxon race led to a "civilization offensive" overseas and was an argument for American expansion to the west and further imperialism, which gained influence at the end of the 19th century.

Manifest Destiny has contributed to the outbreak of the Mexican-American War, the Spanish-American war and the expulsion of the Indians from the west.