There Has Been a Trend Toward Less Government Regulation and Ownership

There has been a trend toward less government regulation and ownership in oligopolistic industries in most industrialized countries since the 1980s.One reason for this is

A) policymakers came to understand that many oligopolistic firms were producing output levels that resulted in allocative efficiency.
B) domestic firms are now exposed to more international competition due to falling transportation and communication costs.
C) Canada's Competition Bureau,and similar agencies in other countries were so successful at promoting competition that such regulation is no longer required.
D) policymakers came to understand that many oligopolistic firms were operating at their minimum efficient scale,thereby producing an efficient outcome.
E) policymakers realized that they did not have effective tools for promoting efficiency.