The correct option is D All of the above
The Pluralist Theory of Democracy states that people with common interest form organised groups to promote their cause and influence the political agenda. It also states that no single group, industry or government agency dominates politics. It describes a political system where there is more than one center of power. The Pluralist Theory and concept of Democracy was promoted by H.J.Lasky, Ernest Barker, and Miss Follette. They were the political theorists.