What is the purpose of the National Mediation Board?

The National Mediation Board (NMB) primarily serves to facilitate labor-management relations within the airline and railroad industries. Its main function is to assist in resolving disputes that arise between employers and employees in these sectors. By providing mediation services, the Board works to promote peaceful negotiations and to help prevent disruptions such as strikes, which can significantly affect transportation and commerce.

While the NMB plays a role in various aspects of labor relations—including overseeing union elections—its principal mission is to ensure that disputes are settled fairly and effectively, thereby maintaining stability in the transportation sectors. This mediation process is crucial because it aims to avoid the escalation of conflicts that could lead to strikes or work stoppages.

The other options presented relate to important aspects of labor relations but do not capture the core purpose of the NMB as accurately as the correct answer. For instance, while managing contracts and overseeing strikes are important components of labor relations, they are not the primary focus of the NMB's established role. The NMB's distinct function in mediating disputes makes it a unique entity in the realm of labor relations within the aviation and railway industries.