Why was manifest destiny so attractive in the 1840's?

From which of the following literary works is this quotation most likely taken?

Hin t in the section titled, "what can be done? " of "battling the digital jolly roger," what is one of the problems caused by piracy that the author lists? he section titled, "what can be done? " of "battling the digital jolly roger," what is one of the problems caused by piracy that the author lists? ow does the writer's point of view in "the completely free market" affect the credibility of the article? a. it's written in the third person, which allows the author to examine all sides of the debate. b. since it's written in the first person, it doesn't objectively present all sides of the argument. c. since it's written in the second person, it puts the reader in the writer's position, and gives the reader more to consider from this perspective. d. it's written in the first person, but is conducted as an interview with several different sources, providing a full-circle debate.

Which would make the best heading for this list of notes about the migration of african-americans during the reconstruction era?