Which of the following is false?

a.

Both frictional and structural unemployment can occur even if unemployment is at its natural level

b.

Cyclical unemployment is unemployment that is in excess of that associated with the natural level of employment

c.

A new college graduate looking for his or her first professional job may experience frictional unemployment

d.

During a business cycle expansion, cyclical unemployment falls

e.

Efficiency wages may cause frictional unemployment