Studies Evaluating the Effectiveness of the Transtheoretical Model of Behavior

Studies evaluating the effectiveness of the transtheoretical model of behavior change indicate that:

A) interventions matched to the particular stage that an individual is in are always successful.
B) interventions to bridge the gap between the preparation and action stages are inadequate.
C) the model's stages are inadequate in analyzing the processes that people go through.
D) the model's applications have shown mixed success.