The Dust Bowl, also known as the Dirty Thirties, was a period of severe dust storms that greatly damaged the ecology and agriculture of the US and Canadian prairies during the 1930s; severe drought and a failure to apply dryland farming methods to prevent wind erosion (the Aeolian processes) caused the phenomenon.
B. Saddam Hussein
<span>Saddam was the fifth President of Iraq, serving in this capacity from 16 July 1979 until 9 April 2003. Hope this helps </span>
I believe the answer is A. Unchecked immigration.