Answer: preemption
Explanation: The National labor Relations Act is a part of the United States labor law which grants workers or employees especially from private organizations the right to self-organization, to form, join or assist labor organizations, form labor unions led by members of their choosing, engage in collective bargaining or meeting relating to the welfare of employees. The National Labor Relations Act was enacted such that employees welfare and rights aren't trampled upon by their employers and ensure they are not forced into doing chores or render services outside the scope of their contract, issues of welfare packages are also addressed collectively.
Preemption or federal preemption may exist when there is a disagreement between federal and state laws regarding a legal issue, the displacement of the state law by the federal law is called preemption due to the supremacy clause which points that the federal law is the Supreme law of the land.
