The answer is C.
As a science website says, "Scientists think they know why the Ancestral Puebloans disappeared. The primary culprit, studies suggest, was a megadrought that would have made it impossible to grow enough food to feed the tens of thousands of people living in the region."
If you didn't know, drought represents the lack of rain.
C. hope it helps man have fun in college
The United Nations was created at the end of World War II as an international peacekeeping organization and a forum for resolving conflicts between nations. The UN replaced the ineffective League of Nations, which had failed to prevent the outbreak of the Second World War.
The Congress of Vienna reorganized Europe after the Napoleonic Wars.
The major goal was to establish a balance between the Five Powers - Austria, Prussia, England, France and Russia -
As a result, the French returned territories gained by Napoleon from 1795 - 1810. Russia extended its powers and received souveranity over Poland and Finland. Austria, too extended its territory.
