Answer :
Final answer:
Among the provided options, the increased investment in European militaries greatly contributed to the start of World War I. This period of militarism led to heightened tension among European powers which eventually ignited the war.
The correct option is c.
Explanation:
Your question is about what factors contributed to the start of World War I. Out of the options you've provided, the answer would be: 'c. the increased investment in European militaries'. This period in history was known as the age of 'militarism', where European powers greatly expanded their armed forces. There was a high-level arms race among the major European powers. A bigger, more equipped military meant better security and dominance. However, it also led to heightened tension and suspicion, thereby laying one of the foundation stones for the start of the war.
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