Which of the Following Best Describes the Cause of "Cyclical

Multiple Choice

Which of the following best describes the cause of "cyclical" unemployment?

A) Firms engage in race,gender and sex discrimination in their hiring practices.
B) Some individuals do not have marketable skills for the jobs that do exist.
C) The AD curve has shifted to the right.
D) The level of overall economic activity has fallen below its potential level.
E) Workers often voluntarily quit a job to look for a better job.