Once a New Behavior Has Passed a Certain Point in the Diffusion

Once a new behavior has passed a certain point in the diffusion process, the influence of nonprofit marketers diminishes because

A) there are many more people to pass along information about the behavior
B) everyone is persuaded, so persuasion is not needed
C) they no longer have the right "target audience mindset"
D) some people can only be influenced by others
E) the old behaviors are so established that nothing will change