An estimated figure of nine million combatants and millions of civilians died as a result of the World War I.
The World War I took place during the early 20th century. It is one of the most dreadful events in the history. Destruction took place throughout the world during the war.
Loss of lives was not uncommon during this event, as about nine million force of the militaries across the world were martyred; and a combat of almost a million people also took place.
Hence, option C holds true regarding the human cost of the World War I.
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