Which of the Following Statements,if True,would Undermine the Theory of Pluralism

Which of the following statements,if true,would undermine the theory of pluralism?

A) Members of Congress have become increasingly dependent on political action committee (PAC) contributions to fund their campaigns.
B) Political action committees (PACs) are not always successful in securing favorable government policies.
C) Membership in labor unions has decreased over the past several decades.
D) Individuals with shared grievances do not always come together to form interest groups.
E) The number of interest groups with lobbyists in Washington,D.C.,has increased over the past several decades.