A. Front is the correct answer
World War I completely changed the way wars were fought.
Trench warfare, which was the norm just a century ago was seen as an nonviable strategy.
Modern machines such as tanks and airplanes made trench warfare mostly about keeping ground and resulted in stalemates.
Also, it was the first time that modern tanks, planes and machine guns were being used for first time at such a large scale, resulting in an unprecedented level of death and carnage.
Military generals soon realized that time-honored military code of conducts were now obsolete and a completely new form of strategy was now required.
C) The Roman adopted many Etruscan ideas, such as some gods and the alphabet
7 SEPTEMBER 1822
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"b. It was vague and its parameters were hard to define" was a criticism made of George H.W. Bush's New World Order, since he only spoke of global governance.