Iron Triangles Are Less Common Today Than They Once Were

 Iron triangles are less common today than they once were because 

A)  agencies today are pressured by so many interest groups. 
B)  they are no longer allowed by many agencies. 
C)  congressional leadership is so much stronger today. 
D)  the courts have stepped in to limit the intervention of interest groups in agency affairs. 
E)  special interests have aligned themselves with congressional leaders.