Final answer:
The decline in U.S. union membership can be attributed to the shift towards service industries, the effects of globalization and foreign competition, and less union-friendly laws like the Taft-Hartley Act. The correct answer is option b. and d.
Step-by-step explanation:
Factors contributing to the decline in union membership in the United States include:
- The shift from manufacturing to service industries, where unionization is historically lower.
- Increased globalization and competition from foreign producers, which have challenged domestic industries and led to job outsourcing.
- Legislation such as the Taft-Hartley Act of 1947 that allowed states to enable workers to opt out of unions, creating a less union-friendly legal environment.
The deregulation of industries also contributed to the decline by removing barriers to entry and increasing competition, which may not favor unionized companies.
Therefore, options b (foreign competition) and d (deregulation) have contributed to the decline in union membership in the United States.