Yeah I think you're correct there
There are no options given, but historically speaking it was the invention of "Cotton Gin".
A cotton gin was a revolutionary invention which enabled people to
easily separate cotton fibers and seeds; previously it used to take a large
time sorting it manually. The inventor behind this was <span>Eli Whitney. The processing was made easy but
still slaves were needed to grow cotton.</span>
<span>British ships began landing supplies of opium in China in the late 1700s and early 1800s, mainly around the mouth of the Pearl River in Guangdong. Opium became more available and more affordable to all levels of Chinese society, even the working classes.
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Answer: It replaced the ineffective League of Nations, which had failed to prevent the outbreak of the second world war
Explanation:
B .........................
