According to the Bureau of Labor Statistics, the four main categories of unemployed workers are

a. discouraged workers, part-time workers, the cyclically unemployed, and the frictionally unemployed.

b. discouraged workers, job losers, new entrants, and the underemployed.

c. new entrants, job losers, job leavers, and reentrants.

d. job losers, job leavers, the structurally unemployed, and the frictionally unemployed.