The graph shows a simple two$-$sector economy whose current output level is $Y_1.$ Which of the statements below correctly describes how the economy moves toward the equilibrium income $Y**?$

A$.$ Since aggregate expenditures at $Y_1$ are greater than real GDP$,$ investment will decrease and real output will fall.

B$.$ Since aggregate expenditures are less than real GDP at $Y_1,$ output will fall.

C$.$ At $Y_1,$ firms will experience unexpected increases in inventories and will increase production until the economy reaches equilibrium.

D$.$ At $Y_1,$ firms will experience unexpected increases in inventories and will reduce production until equilibrium GDP has been attained.

E$.$ At $Y_1,$ firms will experience an unexpected decrease in inventories. In response, they will increase production, and therefore output will rise.