What Is the Difference Between an Issue Network and an Iron

What is the difference between an issue network and an iron triangle?

A) The issue network is an older concept that has been replaced by the theory of an iron triangle.
B) Issue networks involve conflict between members related to an issue, while iron triangles are often viewed as achieving compromise among members.
C) The iron triangle has been eliminated through bipartisan agreement on legislation and replaced by the issue network.
D) Divided government has been pressured by citizens and interest groups resulting in the collapse of the issue network.
E) The iron triangle dealt with Cold War issues, while issue networks pertain to modern terrorist threats.