The correct answer is: D
The National Labor Relations Board (NLRB) is an independent federal agency that governs relationships between businesses, unions and workers. Investigate and provide solutions to illicit practices committed by companies and unions.
I think the correct answer from the choices listed above is option A. One of the most important legacies of the Northwest Ordinance was that it prevented the expansion of slavery in the north of the Ohio River in the newterritories. Hope this answers the question.
The anser is A hope this helped