An Insight into Business Cycles Is Gained by the Fact

An insight into business cycles is gained by the fact that

A) at a peak, autonomous expenditure increases, thereby leading to a recession.
B) at a trough, induced expenditure decreases, thereby leading to an expansion.
C) at a peak, a decrease in autonomous expenditure leads to a decrease in induced expenditure.
D) changes in real GDP result in changes in autonomous expenditures.
E) autonomous expenditure does not change at either a peak or a trough.