I believee the answer is A.
World War I--in the end WWI is connected to the annexation as the Serbian attack on Archduke Franz Ferdinand was a response to the annexation.
Following the Austrian annexation of Bosnia and Herzegovina, Serbian nationalists called the Black Hand planned an attack on the Archduke Franz Ferdinand's visit to Bosnia. This assassination, triggered the events which led directly to the outbreak of World War I.
The banks took money from the common people and passed it on to the wealthy and upper class.
The answer is A. The native warriors went through rigorous and high level challenges mentally and physically. A Sioux’s daily life called for physicality.
It cost the army of Tennessee a lot of soldiers. They had continuous losses for the Confederate Army in a short period of battle. The west force had their military losses too. It was said that the army was ill-prepared of this attack.