Answer:
C.
Step-by-step explanation:
It was his home country. A month after the assassination of the heir to the Austrian throne, Austria-Hungary declared war on Serbia. This action followed a series of ultimatums between not only those two countries but others as well. Austria-Hungary and Germany both had secret agreements to come to each others' aid, and Britain, France, and Russia had similar understandings. These series of secret agreements unnecessarily enlarged the scope and horror of World War I.