One reason: Plowing large areas of land
A few more reasons: poor farming practices, farmers would loosen up the soil, and the land was deforested, making it loose the roots that held the soil in place.
I believe that it would be the second option.
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<span>Assuming that this is referring to the same list of options that was posted before with this question, <span>the correct response would be that it is true that during this time arts and literature flourished in Spain, and it is not true that that Spain was at war with Russia. </span></span>
A. The Soviet Union became an ally of the United States and Great Britain during World War II.