What Has Allowed for the Emergence of Influential Pressure Groups

What has allowed for the emergence of influential pressure groups to develop in states such as Texas?

A) Strong governors who hold considerable power over the legislature are more susceptible to interest group influence.
B) Strong political parties can only emerge through coordination with various interest groups, and as a result, the groups hold considerable influence.
C) Weak political parties in a state are less able to coordinate their activities and are prone to factionalism, off of which interest groups feed.
D) Weak education systems limit the political knowledge of a state's population, which results in interest groups gaining considerable influence.
E) Weak governors have little control over their legislatures and of the state's policy agenda, allowing them to be easily influenced by interest groups.