Which sequence correctly describes the chain of events starting from the assassination of Archduke Franz Ferdinand to Canada's entry into the war?

• A. The assassination of Archduke Franz Ferdinand; Austria-Hungary demanded Serbia; Serbia refused; Austria-Hungary declared war; Russia defended Serbia; Germany declared war on Russia and France; Germany invaded Belgium; Britain declared war; Canada entered the war.
• B. Serbia defeats Austria-Hungary; Russia remains neutral; Germany makes peace with France; Britain remains neutral.
• C. Nationalist movements unify all of Europe; everyone signs a non-aggression pact; World War I is averted.
• D. Germany triggers a trade embargo against Britain; Britain negotiates; war is avoided.

Answer: (A)

This question looks at how a regional crisis escalates into World War I through the alliance system, and how Canada ends up in the war as part of the British Empire.

The sequence in question traces the real chain of events: the assassination of Archduke Franz Ferdinand triggers Austria-Hungary to press Serbia with an ultimatum and then declare war after Serbia’s response. That war draws in Russia, which comes to Serbia’s defense, and Germany joins in due to its alliance with Austria-Hungary, declaring war on Russia and on France. Germany’s decision to invade Belgium brings Britain into the conflict because of the treaty to defend Belgian neutrality. With Britain at war, Canada, as a dominion of the British Empire, enters the war in solidarity with Britain.

The other options skip or reverse these pivotal steps, proposing outcomes that did not occur (such as Serbia defeating Austria-Hungary or a Europe-wide peace without war), or focus on actions that did not lead to a global conflict. The sequence described here best reflects how a local crisis spirals into a global war and explains why Canada joined in.