Which of the Following Best Explains a Major Reason Why

Multiple Choice

Which of the following best explains a major reason why union membership in the United States has fallen in the last 50 years?

A) Legislation provides workers with protections that were once exclusive to unions.
B) Union members earn less on average compared to non-union members.
C) Union membership is too expensive for most blue-collar workers.
D) Foreign-owned manufacturers will not hire union members.