Final answer:
Kaiser Wilhelm II's declaration of war on Russia and Germany's invasion of neutral Belgium, spurred by aggressive foreign policies and a failure of diplomacy, escalated regional tensions into World War I.
Step-by-step explanation:
Actions of Kaiser Wilhelm II Leading to WWI
The actions of Kaiser Wilhelm II that contributed to the outbreak of World War I are multi-faceted. One specific action by Kaiser Wilhelm II that escalated the path to war was his declaration of war on Russia (option c). In the wake of the assassination of Archduke Franz Ferdinand by a Serbian nationalist, a complex web of international alliances and treaties came into play. Germany's aggressive foreign policy and military preparations were well underway. The assassination set into motion a chain of diplomatic failures and military mobilizations. Germany, adhering to its alliance with Austria-Hungary, provided what is known as the "blank check theory," signaling unconditional support, which encouraged Austria-Hungary to declare war on Serbia. Russia then mobilized military forces to support Serbia, leading Germany to declare war on Russia to preempt an alliance of Russia with France against Germany.
This escalation was further exacerbated by Germany's invasion of neutral Belgium as part of its strategy to quickly defeat France. This invasion brought Great Britain into the conflict, due to its treaty of support for Belgian neutrality. Kaiser Wilhelm II's militaristic and aggressive policies, including his quest for a German colonial empire and his disregard for diplomatic solutions, set the stage for World War I, transforming a regional conflict into a catastrophic global war.