The western region of the midwest is dry because it falls in the of the mountains.
a : land fall
b : rain shadow
c : levee
d : gulf stream

The answer is B.

The western region of the Midwest is dry because it falls in the rain shadow of the mountains. 

Hope that helps! :)

Cherokee  removal, part of the trail of tears, refers to the  forced  relocation between 1836 and 1839 of thecherokee  nation from  their lands ingeorgia, south carolina, north carolina, tennessee, texas, and alabama to the indian territory (present day oklahoma)  in  the thenwestern united states, and the resultant deaths