The correct answer is D) Serbian nationalist hoped to drive Austria-Hungary out of Serbian territory.
The sentence that best summarizes the reason that Archduke Franz Ferdinand was assassinated is: Serbian nationalist hoped to drive Austria-Hungary out of Serbian territory.
On June 28, 1914, Archduke Franz Ferdinand and his wife were assassinated in Sarajevo. The Black Hand –a secret society formed by military- where behind the conspiracy to assassinate the Archduke. Due to this incident, the government of Austria issued an ultimatum to Serbia, but Serbia rejected and Austria-Hungary declared war on Serbia. This was the beginning of World War 1.