Recall Application 2, "Two Approaches to Determining the Causes of Recessions

Recall Application 2, "Two Approaches to Determining the Causes of Recessions," to answer the following questions:
-According to the application, a recession caused by a decrease in aggregate demand occurred in:

A) 1973
B) 1929
C) 1979
D) All of the above were caused by a decrease in aggregate demand.