Which of these probably has played the LEAST important role in the drop in unionization rates in the United States over the past 20 years?

Question

Quizplus · Accepted Answer

While the increase in the share of employment by female workers may have affected the makeup and priorities of unions, it is unlikely to have played a significant role in the overall decline of unionization rates. The other three options are more directly related to factors that have contributed to the decline of unionization rates, such as employers' resistance to unionization efforts, shifts in regional employment patterns, and market pressures.

Which of These Probably Has Played the LEAST Important Role