An Important Leading Indicator of Subsequent Changes in Economic Conditions

An important leading indicator of subsequent changes in economic conditions, especially of future developments in industrial production, employment and total spending (GNP) , according to your text, is the:

A) Money supply
B) Rate of interest, particularly rates on corporate bonds
C) Standard and Poor's 500 Composite Index
D) Unemployment rate
E) Dun and Bradstreet's Index of Business Failures
F) None of the above