Which innovation made wwi casualties higher than any other previous war? a)a new defensive tactic known as trench warfare b)a new offensive tactic known as trench advancement c)the formation of alliances on both sides of the war d)the invention of radar that made it easier to spot the enemy

A)a new defensive tactic known as trench warfare

Trench warfare allowed the war to drag on for long periods of time because of the stalemates that ensue from the opposing armies refusing to give up the land under their controls, resulting in high casualties in no man's land.

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Ocean wind pound most of Siberia.