Which of the following statements about economic fluctuations is true?
a. A recession is when output rises above the natural level of output.
b. A depression is a mild recession.
c. Economic fluctuations have been termed the business cycle because the movements in output are regular and predictable.
d. A variety of spending, income, and output measures can be used to measure economic fluctuations because most macroeconomic quantities tend to fluctuate together.
e. All of the answer choices are correct.