Question

What happened after the assassination of Archduke Franz Ferdinand that led to ​ World War I ​ ?

Troops that had been protecting him attacked Serbian military positions.

Serbia rejected a list of Austrian demands, leading to the outbreak of war.

Diplomatic relations ended between Germany and Austria, leading to war.

Russian troops invaded Serbia, seeking revenge for the death of the czar’s cousin.

Answer 1

Answer: The murder of Archduke Franz Ferdinand outraged Austria-Hungary. ... Austria-Hungary was furious and, with Germany's support, declared war on Serbia on July 28. Within days, Germany declared war on Russia—Serbia's ally—and invaded France via Belgium, which then caused Britain to declare war on Germany.