Wealthy Landowners
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there were two technological innovations that profoundly changed daily life in the 19th century: steam power and electricity. The railroad helped expand the U.S.. The telegraph, the telephone, and the typewriter brought people together that were far away.
Answer:
C. Chemical weapons.
Explanation:
TL:DR Chemical gas is a war crime due to the amount of suffering it causes. Mustard gas burns the skin, Phosgene is impossible to see, and Chlorine can make you drown in your own body.
Machine guns had been in use and invented since 1908, with invention of weapons such as the Vickers and German Maschinegewehr 08. Trench warfare wasn't a weapon, but more of a tactic. Mines weren't a war crime either as they most likely weren't deemed to cause "unneeded suffering" and their purpose usually was to simply discourage the travel of an area. Usually, if you stepped on a mine you'd die.
Meanwhile, Chemical gas was simply invented on accident as the German Empire's scientist,
