The correct answer is B. The Apache tribe.
Black slaves gained their freedom.
The best answer is A.
In 1903, the United States supported a rebel group from Panama which was then part of Colombia.
The US signed a treaty with Colombia called the Hay - Herran treaty which granted the USA use of the canal on its completion.
The Colombian government refused to sign for fear of losing sovereignty and the US responded by approving a rebellion by Panama nationalists which started on November 1903.
The US sent a battle ship to Panama to " protect American lives" in Panama making Colombian forces afraid to sail to Panama to quell the rebellion. The rebellion succeeded and Panama declared itself independent from Colombia.
Interchangeable parts, popularized in America when Eli Whitney used them to assemble muskets in the first years of the 19th century, allowed relatively unskilled workers to produce large numbers of weapons quickly and at lower cost, and made repair and replacement of parts infinitely easier.
