Which of the Following Explains the Cause of the Change

Which of the following explains the cause of the change in the unemployment rate at the end of a recession?

A) Firms are hesitant to rehire laid off workers as they continue to operate below capacity.
B) Firms rapidly hire new workers at the first sign of on an increase in demand for their goods.
C) Discouraged workers return to the labor force and this makes the unemployment rate fall.
D) Discouraged workers leave the labor force and this makes the unemployment rate rise.