Answer: A. Klan members had official and unofficial political power
Step-by-step explanation:
Klan members in the 1920's had succeeded in getting into political positions and they also had political backers in various states. This gave them both official and unofficial political power and therefore made it difficult to go after them.
This was added to the fact that Klan activities in terrorizing Black Americans was not frowned upon in public by the white population of Southern America so they felt emboldened to continue.