The Opium Wars were a series of wars between Chine and Great Britain. It started when Chine started to refuse the shipments of Opium. The war was a fail for China, this means that answer A, C, and D are wrong. The only answer left is B. Please contact me if you want more information on the opium war.
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a rail roads this is why they built the railrod in the 1850 that was almost through the whole reaches of the us