It is now believed that the largest contributing factor to the decline of the Indus Valley civilization was an outbreak of disease--since there were no treatments and the density of the civilization led the disease to spread very quickly.
The Potsdam Conference<span>, </span>1945<span>. The Big Three—Soviet </span>leader<span> Joseph Stalin, British Prime Minister Winston Churchill (replaced on July 26 by Prime Minister Clement Attlee), and U.S. President Harry Truman—met in </span>Potsdam<span>, Germany, from July 17 to August 2, </span>1945<span>, to negotiate terms for the end of World War II.
Hope I Helped :D
-Nullgaming650
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Sooners were settlers who sneaked into Oklahoma before the Land Rush of 1889. So the answer would be C. Hope this helps :)