Trench warfare led to stalemates during world war I by making it

Which of the following resulted from the passage of the dawes act in 1887?

Following archduke franz ferdinand's assassination, austro-hungarian leaders: a. aided the ottoman empire in its campaign to keep serbia under its control. b. executed nearly all prominent serbs living in austria-hungary c. threatened to invade serbia if serb leaders did not agree to a set of strict demands. d.. formed an alliance with great britain to protect austria-hungary from future attacks.

How did political revolutions in the atlantic ocean basin affect or alter the institution of slavery and the lives of slaves