What is the name of the act that imposed several restrictions and requirements on unions?

The Labor Management Relations Act, also known as the Taft-Hartley Act, was enacted in 1947 and is significant because it established various regulations and restrictions on union activities and operations. This legislation was aimed at balancing the rights of both employees and employers in the context of labor relations. Among its provisions, the act includes measures that limit union power, such as prohibiting secondary boycotts, jurisdictional strikes, and closed shops. Additionally, it requires unions to disclose financial and administrative practices, thereby increasing transparency. This act was a response to rising concerns about labor unrest and the power of unions post-World War II, making it a critical law in the landscape of U.S. labor relations.

In contrast, the other options refer to either broader collective bargaining legislation or specific aspects of union operations but do not encompass the comprehensive restrictions and requirements imposed specifically by the Labor Management Relations Act.