Identify a true statement about union management relations in the United States.

a$.$ In the United States, labor unions typically provide training programs that improve worker readiness.

b$.$ In the United States, management and labor traditionally take the roles of competing adversaries who often clash to reach agreement.

c$.$ In the United States, union agreements are made for only one year because of political and social instability.

d$.$ In the United States, unions focus exclusively on activism and integration with ruling governmental and political powers.