All of the following played an important role in the outbreak of World War I EXCEPT which one?
A. ethnic tensions particularly in Eastern Europe
B. competition between imperialist nations
C. an exaggerate sense of nationalism
D. a deadly flu pandemic
All of the following played an important role in the outbreak of World War I except "D. a deadly flu pandemic," since the spread of disease had no impact on the rise of either nationalism or militarism.