Trench warfare began after germany failed in its initial plan to seize france and bring a quick end to the war. negotiate a temporary truce with the allied forces. attack the allies by sea with its powerful navy. storm across the eastern front to attack russia

The correct answer is: "Trench warfare began after Germany failed in its initial plan to seize France and bring a quick end to the war".

In fact, the initial phase of WWI is frequently denominated "lightning war", as this was exactly the strategy followed by Germany, that attempted to quickly invade France and end the conflict. German expectations were not fulfilled, and the French were able to contain the attack. In this moment, the Western Theatre of WWI stagnated. The trenchs were dug and almost no advances could be made by any of the two combatants in quite a while.

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