The Figure Below Shows the Aggregate Demand and Supply Curves

Multiple Choice

The figure below shows the aggregate demand and supply curves for the U.S.The figure given below shows that between period 1 and period 2 nominal GDP changed from $40,000 to:​ ​
Figure 5.2
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A) $18,000 and back again.
B) $18,000 and stayed there.
C) $18,000 in period 1 and to $10,000 in period 2.
D) $10,000 in period 1 and stayed there in period 2.
E) $10,000 in period 1 and to $18,000 in period 2.