Which of the Following About Business Cycles Is True

Which of the following about business cycles is true?

A) A "depression" is a recession that is mild and relatively brief.
B) The expansions and contractions of real world business cycles last varying lengths of time.
C) The timing of business fluctuations is regular and, therefore, easily predictable.
D) During the recessionary phase of the business cycle, the rate of unemployment is generally quite low.