How did technology affect the war?
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Technological developments in engineering, metallurgy, chemistry, and optics had produced weapons deadlier than anything known before. The power of defensive weapons made winning the war on the western front all but impossible for either side. As the explosive advanced and radius of bombs increased, the military's become more vulnerable to it. Artillery, naval gun fire, attack helicopters and fighter craft were the next advanced warfare technologies that were used in killing the enemies. They played a significant role in the way war was fought.

d: social contract theory

c, because the american revolution was from 1765 to 1783.