This is math
Fraction of Americans= 140/216
=70/108
Simplest form=35/54
The appropriate response would be D. The Dust Bowl is a natural calamity that hit the Midwest in the 1930s. Broad cultivating joined with severe drought caused the it. Deep plowing on the Great Plains executed the common grasses that kept soil set up, and the topsoil swung to dust and blew away.
Since this is Abnormal Psychology, her therapist is using the family systems perspective to help Sally out.