Answer: Answer A
Explanation: " Harsh conditions on most reservations made hunting and farming for subsistence impossible, leading to conflicts over access to resources" does not talk about hostilities between the US government and American Indians living on reservations.
<span>This is also known as the Amritsar Massacre. On April 13, 1919 a group of nonviolent protesters and pilgrims were gathered in Jallianwala Bagh were shot at by troops form the British Indian Army. After the massacre Indians wanted their full independence and not just the self-rule they had been demanding of the British Empire.</span>
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.
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